My calculator says it's true

Is the following equation true?

398 7 12 + 436 5 12 12 = 4472 \sqrt[12]{3987^{12} + 4365^{12}} = 4472


Hint: How is this related to Fermat's last theorem ?

Yes Sometimes No

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35 solutions

Pi Han Goh
Mar 8, 2014

I have discovered a truly marvellous proof of this, which this margin is too narrow to contain.

You have a huge space to type in!

Don't make someone else spend 7 years of Sundays to solve your problems.

Calvin Lin Staff - 7 years, 3 months ago

I see what you did there :D

Vaibhav Nayak - 7 years, 3 months ago

I saw a video on Numberphile about this, so I just solved this "Fermat's Last theorem" problem without even thinking about it

Gurvir Singh - 7 years, 3 months ago

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the video featuring simon singh :)

Biswarup Sahoo - 7 years, 2 months ago

Haha...LOVE YOUR RESPONSE.... ;). !!!!

Tanya Gupta - 7 years, 3 months ago

Aww I'm too late. It's the cheekiest remark any mathematician could write

Spock Weakhypercharge - 7 years, 2 months ago

Arrgghh!Mr Fermat has risen from the dead!And he is now very angry with the setter of this question for violating his theorem!!!

King Zhang Zizhong - 7 years, 3 months ago

To be fair to Fermat: He did actually prove that the Diophantine equation x 4 + y 2 = z 4 x^4+y^2=z^4 has no positive integer solutions ("Fermat's Right Triangle Theorem"); this suffices to prove that our equation here is wrong. Fermat's proof is rather simple, by infinite descent.

Otto Bretscher - 6 years, 1 month ago

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Maybe I should change my equation to this: 4332 9 19 + 5114 4 19 19 = 51257 \large \sqrt[19]{43329^{19}+51144^{19}}=51257 .

Pi Han Goh - 6 years, 1 month ago

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People knew by the end of the 1800s that there are no solutions for n=19. Maybe you should post this example:

"Counterexample to Fermat's Last Theorem Found!!! There has been a really amazing development today on Fermat's Last Theorem. Noam Elkies has announced a counterexample, so that FLT is not true after all! His spoke about this at the Institute today. The solution to Fermat that he constructs involves an incredibly large prime exponent (larger that 10^20), but it is constructive. The main idea seems to be a kind of Heegner point construction, combined with an really ingenious descent for passing from the modular curves to the Fermat curve. The really difficult part of the argument seems to be to show that the field of definition of the solution (which, a priori, is some ring class field of an imaginary quadratic field) actually descends to Q. I wasn't able to get all the details, which were quite intricate... So it seems that the Shimura Taniyama conjecture is not true after all. The experts think that it can still be salvaged, by extending the concept of automorphic representation, and introducing a notion of "anomalous curves" that would still give rise to a "quasi-automorphic representation". "

This e-mail circulated in April, 1994, hitting the mathematical community like a bombshell.

Otto Bretscher - 6 years, 1 month ago

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@Otto Bretscher Speaking of April Fools' .

Pi Han Goh - 6 years, 1 month ago

can anyone tell that why calculator is giving wrong answer

Aman Gupta - 7 years, 3 months ago

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It doesn't show the last few digits of the number

Josh Speckman - 7 years, 2 months ago

The screen is too short

Lâm Lê - 1 year ago

Hahaha This made me smile.

Matt Remmie - 7 years, 2 months ago

My iPad is clever enough to say it is not true XD (just kidding)

Takeda Shigenori - 7 years, 2 months ago

Fermat's Last Theorem huh.

Renz Ian Dahildahil - 7 years, 3 months ago

Wow

Arkapravo C'borty - 7 years, 3 months ago

Oh god that's amazing? Do you want to come over to my house for dinner?

Joshua Ong - 7 years, 2 months ago

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Do you want to come to MY HOUSE for dinner?(Btw, I will bring Mr Fermat along with me)

King Zhang Zizhong - 7 years, 2 months ago

That's a lot of likes BTW.

Joshua Ong - 7 years, 2 months ago

Something similar to this was featured in an episode of the Simpsons as a freeze frame gag

Ying Cen Tee - 7 years, 2 months ago

plzzz type ur solution.....

saurabh kumar agrawal - 7 years, 1 month ago

2.5 years late pffff

Utku Demircil - 4 years, 9 months ago

150th upvote.

Rohit Kumar - 4 years, 9 months ago

Subtle reference. I like that.

Jase Jason - 4 years, 4 months ago

What margin!?!?

Lâm Lê - 1 year, 1 month ago

🤣

Mahdi Raza - 2 months, 1 week ago

please sollllluttttion

rajat kharbanda - 6 years, 1 month ago

this is wrong

AJESH K.C - 7 years, 3 months ago

it is easy with ancient indian mathematical methods, just for few seconds.

Prabal Pratap - 7 years, 3 months ago

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how

Ahmed Abd Almenam - 7 years, 3 months ago

Please do not talk like Fermat

Adhiraj Mandal - 7 years, 2 months ago

If Calculator say,s it True, It is true. We don't have time to waste.

Shahid Qureshi - 7 years, 2 months ago

THE "NO" is not Correct at all: PROOF IS AS UNDER: (3987) Power 12 = 1.61345E+43 And (4365) Power 12 = 4.78422E+43 SUM of both = 6.39767E+43 and 1/12 power of this sum is = 4472 ANSWER = Correct Now you prove How Your "NO" is right answer.

Shahid Qureshi - 7 years, 2 months ago

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By your logic, 1 0 100 + 1 = 1.0000000 E + 100 = 1 0 100 10^{100} + 1 = 1.0000000\text{E}+100 = 10^{100} ?

Pi Han Goh - 7 years, 2 months ago

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My logic is: 2+2=4. Be a bit smart and put the figers on an Excel Sheet. You will get the answer. If you can't do it, allow me to send you a soled sheet.

Shahid Qureshi - 7 years, 2 months ago

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@Shahid Qureshi figers? Are you under the impression that 398 7 12 3987^{12} is EXACTLY equals to 1.61345 E + 43 1.61345\text{E}+43 , that is 161345 161345 followed by 38 38 zeros?

Pi Han Goh - 7 years, 2 months ago

@Shahid Qureshi A Very Close Value is 4472.0000000070592907382135292414.............. Your Calculator has a limit to its solving ( ALU)] It isn't a SUPERCOMPUTER... So it gives the value 4472.

Jayesh Narayan - 7 years, 2 months ago

@Shahid Qureshi Your calculator may not have enough computing power (or space for that matter) to show you that 398 7 12 3987^{12} + 436 5 12 4365^{12} \neq 447 2 12 4472^{12} , however it is still the case. Andrew Wilson devoted ~ 8 years of his life studying Fermat's Last Theorem before actually proving it. This equation is just a classic example of a "near miss"

Curtis Clement - 6 years, 5 months ago
Trevor B.
Mar 8, 2014

This is a pretty funny problem, actually. Obviously, it is not true, because it is a violation of Fermat's Last Theorem. This is known as a "Fermat near miss." A calculator will tell you that two sides are equal, but there are digits of the numbers after what the calculator will tell you that are not equal.

Another way to tell that the two sides aren't equal is to take both sides mod \text{mod} easy to work with numbers. Taking each side mod 2 \text{mod }2 and mod 10 \text{mod }10 is inconclusive. The left side, if it is in fact an integer, would be divisible by 3 , 3, because 398 7 12 3987^{12} and 436 5 12 4365^{12} are both divisible by 3 12 . 3^{12}. However, 4472 4472 is not divisible by 3 , 3, so 447 2 12 4472^{12} is not divisible by 3 3 either.

You can learn more about Fermat near misses in this video from Numberphile.

4472.0000000070592907382135292414 is shown on the built in windows calculator (in scientific mode) as well.

Dennis Kamber - 7 years, 2 months ago

"4472.0000000070592907382135292414" my calculator shows this answer

Aman Agrawal - 7 years, 3 months ago

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Also my calculator !!

Mariem Khemili - 7 years, 3 months ago

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nice calculators you have there

Jean Lille - 7 years, 2 months ago

Well, your solution made me surprised.

Thích Thảo - 7 years, 3 months ago

its interesting . . .

Farooq Aslam - 7 years, 3 months ago

4472.00000000705929073821352924144940938473689768243066193961642581181025581885700714287170250554382069429582978299441080874096124021069957716998872663907962296431554357370519777805996171723726873723895550703256163015599978925231864156945746330729296709617573546234696486722883526954706549688647708965890355416153360578483743865023322087991303360001545248892550530101179201344015254568815004647122533141124865366231474398118382385646519298957829692820294466440752408088741495353094594240751299208103842907790120879354443178547330904068246634799214124036844643899981466363103635221029984559572026881320085843110509687974580329527428712778221196482298636529156961890546177104351929381646284348949856379387927889786214889494336304702972916145701797916075949731377452325426442384582080670846852966226394459062885518774269721150718650924915340845454847050987309270260943371547580716473501436797000996092554378715154386056687623374665873048095225900066605217843514418386106226366791172271857353915543522625242381042518035396676829304547547661970150191084887024514730257736165461418980986991366188741269759124952624368025418658144975473457357094268568563177641848621836361918288088986901553603949355305848565522947722946779068564706691645147427915176011156985158437434121939584540566628901991658402333117089599241923811441051760278628155842375455876997322954901325573437113676372586235991383607653151972089823668655812106720553228013216891030669705585942652040870708041498994509995345398409434912078187074109921563782302599790321012687210119607856286555248347166690956073756037660533241341253797385846743038902222880457337526013674124382892179060097223819944821947255846444093446469211393903922665302563848020884624709653053558861665062013535731898257916891448570738776880265190165332834318814898501051252318979364304470988335681295334613412831928393041945728744973497967482663235028835750414395158361107453678819799830067806892105001235995363061224693815121540432188989876772037870954646042523040602881724388461708631350316591666251043203755280519444456775347811976036989008801919480798029133860328763750328264537137921647841843130320047355441436043981313113204731839816432986010054299809989517480246671830541238460902771513747072999914594415815121765415519188513596281537318165888976563493616883065442445248000908496262180821906952597953214615826332512574071391355711076451650772343211490967121225512139704982921391483009258055676069128575330485367969401517273445546755846667126184268495008266037227034558476519596345672455243986567853357559724077449332372760220104575202695584385525212737040354110017035143663166110957381365686645095144893100591047367214647318884982646331226821024405791595477692022522004175947741283952683918724736363721843010997237448130313721714901472359276796291337714349406451086860783312799849134559524885920123139587429240932906448297824279503476548278839556695480264182922888138817049255379260039013331510816637984336452729389763009256242512256693018630747298257212510234186999277455928744133124454509367522895238130019461530283951284580263746227615755243797836823184338119084079520405312589456856867637273025556191023877266243419099859462655098642665159637801376957506795618899909016767481125072449652046388982490801557549327685225456305814600467480801955640335025070359710247829806606014017686568615377634… :-)

Ginasio Mental - 7 years, 1 month ago

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4472.000000007059290738213529241449409384736897682430661939616425811810255818857007142871702505543820694295829782994410808740961240210699577169988726639079622964315543573705197778059961717237268737238955507032561630155999789252318641569457463307292967096175735462346964867228835269547065496886477089658903554161533605784837438650233220879913033600015452488925505301011792013440152545688150046471225331411248653662314743981183823856465192989578296928202944664407524080887414953530945942407512992081038429077901208793544431785473309040682466347992141240368446438999814663631036352210299845595720268813200858431105096879745803295274287127782211964822986365291569618905461771043519293816462843489498563793879278897862148894943363047029729161457017979160759497313774523254264423845820806708468529662263944590628855187742697211507186509249153408454548470509873092702609433715475807164735014367970009960925543787151543860566876233746658730480952259000666052178435144183861062263667911722718573539155435226252423810425180353966768293045475476619701501910848870245147302577361654614189809869913661887412697591249526243680254186581449754734573570942685685631776418486218363619182880889869015536039493553058485655229477229467790685647066916451474279151760111569851584374341219395845405666289019916584023331170895992419238114410517602786281558423754558769973229549013255734371136763725862359913836076531519720898236686558121067205532280132168910306697055859426520408707080414989945099953453984094349120781870741099215637823025997903210126872101196078562865552483471666909560737560376605332413412537973858467430389022228804573375260136741243828921790600972238199448219472558464440934464692113939039226653025638480208846247096530535588616650620135357318982579168914485707387768802651901653328343188148985010512523189793643044709883356812953346134128319283930419457287449734979674826632350288357504143951583611074536788197998300678068921050012359953630612246938151215404321889898767720378709546460425230406028817243884617086313503165916662510432037552805194444567753478119760369890088019194807980291338603287637503282645371379216478418431303200473554414360439813131132047318398164329860100542998099895174802466718305412384609027715137470729999145944158151217654155191885135962815373181658889765634936168830654424452480009084962621808219069525979532146158263325125740713913557110764516507723432114909671212255121397049829213914830092580556760691285753304853679694015172734455467558466671261842684950082660372270345584765195963456724552439865678533575597240774493323727602201045752026955843855252127370403541100170351436631661109573813656866450951448931005910473672146473188849826463312268210244057915954776920225220041759477412839526839187247363637218430109972374481303137217149014723592767962913377143494064510868607833127998491345595248859201231395874292409329064482978242795034765482788395566954802641829228881388170492553792600390133315108166379843364527293897630092562425122566930186307472982572125102341869992774559287441331244545093675228952381300194615302839512845802637462276157552437978368231843381190840795204053125894568568676372730255561910238772662434190998594626550986426651596378013769575067956188999090167674811250724496520463889824908015575493276852254563058146004674808019556403350250703597102478298066060140176865686153776347693193651075246504395449951947550979431748418295033001958301674582110752521983891508092252995563532505823180530485770354979735072322716289403092361325982373344359296985307236929497424644194948060513528018610894602995813485495476102438035180686093171916860809233941114482178315418616359814901083901420479927286526030189105570865647400029012097365761607116235643980959902726751046144556431217699836591847068948753997186024856398551248856126704980069240223373962014564717448894506579142489504864407208201112796066478817324478027509645361160782344535038143393807554481484761250462888983835519770472182006373870457711788317497594991191691997956790858947437007626770630555115060430092539861265567118641791841190962212066821854526659792492557211119958746030782958151068055658627452633173156947215424480706559816646250006486716552365195640569569856074685756383944352468642021866661067334443687492789896161606210618536806969015309141324366549797143948973237120380164744724746903023718786082148614703597160886311023790090136138675464586719722882497106126531596387330239684787359694931787349098965605287299801028328373420884478820157918353378048632976872779120770601939582075472098655650052634953412570780833995054521709306987389232818413551372315304121225126986564702379647691692825868802772433315051740156975480689889389628188906111377447165249154761687384469582987565276539423543151057351831392180063818590618259977722798402047287923091829969991264194642730637524188633944574845648303131103420779818337085970938196297509668156410231473481555097397269195825635753918091385643052123358294092638577406130470553680363487983372248726636199131183906629091358344774267622793277855733780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9

Arulx Z - 5 years, 2 months ago

If one knows the cube and fourth-power cases of FLT as being more reliable (as it were), then there's an easier way to check the 12th-power case, since x^12 = (x^3)^4 = (x^4)^3.

Whitney Clark - 4 years, 9 months ago

The FLT near-misses are sort of analogous to Pell's Equation (PE)

b² = na² + 1

Here's what I mean. When n is a positive non-square integer (+NSI), the ancient reductio-ad-absurdam proof of Euclid says that

b² = na²

has no positive integer (+I) solutions, (a,b), on the way to proving √n is irrational. Solutions of PE and the associated Pell's Equation (APE)

b² = na² - 1

can be considered "Euclid near-misses." BTW, PE has +I solutions for every +NSI, n; [note that (0,1) is always a solution, but not a positive one, because of the 0] the APE has solutions for infinitely many +NSI's (e.g., 2, 5, 10, 13); but lacks solutions for infinitely many others (e.g., 3, 6, 7, 11).

Fred Shuman - 4 years, 9 months ago
Soumya Patra
Mar 13, 2014

Assuming it to be true

3987^12 = 4472^12-4365^12 = (4472-4365)(.........) = 107 * (..)

Since 3987 is not divisible by 107, it has to be false

That is another way of thinking about it...well done!!

Tanya Gupta - 7 years, 2 months ago

Nice. I also solved in the same way..

Mahesh Bongani - 7 years, 2 months ago
Anish Puthuraya
Mar 8, 2014

A violation of Fermat's Last Theorem

Without resorting to Fermat's Last Theorem, can you find an elementary proof?

Also, why would the calculator tell you that?

Calvin Lin Staff - 7 years, 3 months ago

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odd number^12 = odd number

odd number^12 + odd number^12 = odd number + odd number

but when we add two odd numbers the is divisible by 2 but not 4 or 8.

therefore we can write

2*odd number= odd number^12 +odd_number^12

when we take the twelfth root of this we should get an irrational

number because there is only one 2 as a factor of that number.

torque omega - 7 years, 3 months ago

I suppose that the calculator approximated it...I checked it on wolfram alpha...It give a value of 4472.000000007059 4472.000000007059

And about the elementary proof, I do not know...Do you? If so, would you be so kind to tell me?

Anish Puthuraya - 7 years, 3 months ago

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Hint: m o d 3 \bmod {3}

Pi Han Goh - 7 years, 3 months ago

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@Pi Han Goh Perfect.

I was thinking of the special case of Fermat's Last theorem when n = 3 n = 3 or n = 4 n =4 .

Calvin Lin Staff - 7 years, 3 months ago

@Pi Han Goh Of course...Thank you...
The LHS is divisible by 3, while the RHS is not..

Anish Puthuraya - 7 years, 3 months ago

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@Anish Puthuraya Hi Anish! How did you deduce that the left hand side is divisible by 3?

Mark Mottian - 7 years, 3 months ago

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@Mark Mottian You would need to know the concept and the properties of Modular Arithmetic for this.

Note: Read all the properties of Modular arithmetic from the link that I have provided.

Raise to the power 12 12 on both sides and,
We take ( m o d 3 ) \displaystyle \pmod 3 on both sides.

( 398 7 12 + 436 5 12 ) ( m o d 3 ) = 447 2 12 ( m o d 3 ) (3987^{12}+4365^{12})\pmod 3 = 4472^{12}\pmod 3

398 7 12 ( m o d 3 ) + 436 5 12 ( m o d 3 ) = ( 4472 ( m o d 3 ) ) 12 3987^{12}\pmod 3+4365^{12}\pmod 3 = (4472\pmod 3)^{12}

( 3987 ( m o d 3 ) ) 12 + ( 4365 ( m o d 3 ) ) 12 = 2 (3987\pmod 3)^{12} + (4365\pmod 3)^{12} = 2

0 + 0 = 2 0+0 = 2

Since this equation is not true,
thus the given equation is False.

Anish Puthuraya - 7 years, 3 months ago

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@Anish Puthuraya Also check this link for more deep understanding of it.

Anish Puthuraya - 7 years, 3 months ago

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@Anish Puthuraya Thank you so much Anish!

Mark Mottian - 7 years, 3 months ago

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@Mark Mottian You're welcome.

Anish Puthuraya - 7 years, 3 months ago

@Anish Puthuraya In this it can be deduced even without modular arithmetic as both 3987 3987 and 4365 4365 are divisible by 3 3 .

Eddie The Head - 7 years, 2 months ago

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@Eddie The Head In this case it works but not always I suppose

Mardokay Mosazghi - 7 years, 2 months ago

@Pi Han Goh mod 4 helps too.

Jubayer Nirjhor - 7 years, 3 months ago

calculation vise it is correct buts this is against the Fermat's Last Theorem.so these three numbers prove this law wrong which states that In number theory, Fermat's Last Theorem (sometimes called Fermat's conjecture, especially in older texts) states that no three positive integers a, b, and c can satisfy the equation a^n + b^n = c^n for any integer value of n greater than two.

Engr Rehan Khan Khattar - 7 years, 3 months ago
Otto Bretscher
Apr 28, 2015

This is known as Homer's Last Theorem from the Simpsons (the episode was "Wizard of Evergreen Terrace"

The equation above and the inequality below are also quite interesting...

Eddie The Head
Mar 24, 2014

The LHS is clearly divisible by 3 but the RHS is not !! Buy a better calculator mate!! :D :D

Soumya Ananthula
Mar 24, 2014

9 is a common factor for both 3987 and 4365.. taking the common factor out of the root, implies that 4472 should be divisible by 9.. but it is not.. hence the given equation doesn't hold good.

Abd Fml<3
Aug 21, 2018

398 7 12 + 436 5 12 12 = 4472 \sqrt[12]{3987^{12} + 4365^{12}} = 4472 ,

then 398 7 12 + 436 5 12 = 447 2 12 3987^{12} + 4365^{12} = 4472^{12}

Or by Fermat's last theorem : there is no three positive integers x x , y y , z z , that satisfy x n + y n = z n x^n + y^n = z^n

Ashtamoorthy Ts
Aug 21, 2018

if true, then 3987^12+4365^12=4472^12, and obviously is a violation of Fermat's theorem

According to Fermat's Last Theorem, for integers n > 2 n > 2 , there are no integers a a , b b , and c c for which a n + b n = c n a^n + b^n = c^n . Since, 12 > 2 12 > 2 , there cannot be integers a a , b b , and c c such that a 12 + b 12 = c 12 a^{12} + b^{12} = c^{12} .

Therefore, there is no integer c c where 398 7 12 + 436 5 12 = c 12 3987^{12} + 4365^{12} = c^{12} , meaning that there is no integer c c such that 398 7 12 + 436 5 12 12 = c \sqrt[12]{3987^{12} + 4365^{12}} = c . Thus the value of 398 7 12 + 436 5 12 12 \sqrt[12]{3987^{12} + 4365^{12}} is not an integer, while the above equation asserts that 398 7 12 + 436 5 12 12 \sqrt[12]{3987^{12} + 4365^{12}} is equal to the integer 4472 4472 , meaning that the above statement is false .

Nicely written! +1

Bonus question: Can you find another triplet of positive integers ( a , b , c ) (a,b,c) and a positive integer n > 2 n>2 such that a n + b n n \sqrt[n]{a^n + b^n} is almost equal to c c ?

Pi Han Goh - 3 years, 2 months ago

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1. n = 3 n=3

( a , b , c ) = ( 193284753450 , 111554534545 , 204952637451 ) (a,b,c) = (193284753450,111554534545,204952637451)

Note that @Pi Han Goh, if you simply plug in extremely large (around 12-digit) numbers and use n = 3 n=3 , many calculators will simply give an integer output (or, sometimes, state "Error: Overflow"). (This was how the above example was calculated.)

Out of curiosity, does this mean that using large numbers simply makes a n + b n n c \sqrt[n]{a^n + b^n} \approx c (for integers c c ), or is this just caused by the rounding performed by the calculator?

In addition, based on my method, you would need two 22-digit numbers to make a 12 + b 12 12 c \sqrt[12]{a^{12} + b^{12}} \approx c for integers c c . Can you show me how you got such a simple but powerful example of a Fermat near miss using only 2 2 four-digit numbers and n = 12 n=12 ?

Infinity Mathematics - 3 years, 2 months ago

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or is this just caused by the rounding performed by the calculator?

Rounding error.


How can we generate triplets of a , b , c a,b,c with suitable n n such that it's a near miss? See this .

See other articles like this too and this one too .

Pi Han Goh - 3 years, 2 months ago

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@Pi Han Goh Ok thanks!

Also, is it possibly to prove that there are infinite Fermat "near-misses" of the form a n + b n n c \sqrt[n]{a^n + b^n} \approx c or a n + b n c n a^n+b^n \approx c^n for which a n + b n c n \frac{a^n+b^n}{c^n} is extremely close to 1 1 (say, at most 0.000000001 0.000000001 away from 1 1 )?

Infinity Mathematics - 3 years, 2 months ago

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@Infinity Mathematics Yup! Read the last article I've linked above. It shows that we can easily generate infinitely many values of x , y , z x,y,z satisfying x 3 + y 3 = z 3 ± 1 x^3 + y^3 = z^3 \pm 1 .

Pi Han Goh - 3 years, 2 months ago
Sumit Dhadam
Mar 29, 2014

Since it's just asked to check the correctness we could check by considering the common factors on both the side. Now for LHS Nos, we get 3987 = 1329 * 3 and 4365= 1455*3, raising to power 12 and taking 3^12 common LHS becomes multiple of 3 where RHS which is 4472 isnt. SO it must be false. Simple...!

Pranav Natu
Mar 29, 2014

fermat's last theorem

Saurabh Mallik
Mar 27, 2014

Actually the value of: ( 398 7 12 + 436 5 12 ) 1 / 12 = 4472.0000000070592 ( a p p r o x . ) ({3987^{12} + 4365^{12}})^{1/12} = 4472.0000000070592 (approx.)

Thus, ( 398 7 12 + 436 5 12 ) 1 / 12 ({3987^{12} + 4365^{12}})^{1/12} is not equal to 4472 4472 .

So, the answer is N o \boxed{No} .

Use logarithm, and solve with appoxrimate values.

Dileep Reddy
Mar 13, 2014

Easiest way to think is LHS is divisible by 3, but RHS is not

Bala Tweakbytes
Mar 13, 2014

I did this very basically. Not applying any fermat principles here. from 4365 I wrote it as 3987+378 so it becomes 12th root of:- 3987^12+(3987+378)^12 Now from the second bracket too 3987 common to give, 3987^12+3987^12(1+0.094), ignoring 0.094, just for convinience, we get 3987 12th root of 2 which is 3987 1.05 which is 4186 which led me to answer. Of course I had seen the Numberphile video but this was just some simple method I used. I do agree its not the best of mathematical methods as difference between idealized answer and calculator answer are not very far but I reasoned that 0.094 will not have affected 12th root much. I Can be wrong here though, correct me as needed.

Pulipati Babu
Mar 13, 2014

this is not (a+b)^2 type to take out a+b from root, it is a^2 + b^2 at any cost find out a^12 value and b^12 value add them then go for 2x2x......... from that take out one number of 12 same nos. if it is perfect 12th root we will get nos. without remain odd multiply selected nos result is answer

2 3 24 17 11593 32353 85313 208212548830074457 2\ 3^{24}\ 17\ 11593\ 32353\ 85313\ 208212548830074457 , not even close.

It's because the calculator can't show all the digits so it truncates all but the last few digits also FLT

Abhinav Prakash
Aug 31, 2016

Because no number greater than 2 exist which satisfy x^n+y^n=z^n

Lukas Leibfried
Aug 31, 2016

If x n + y n = z n , n > 2 , n Z , x y z 0 x^n + y^n = z^n, n > 2, n \in \mathbb{Z}, xyz \neq 0 , then there are no solutions for ( x , y , z ) (x,y,z) such that x , y , z Z x,y,z \in \mathbb{Z} .

Matthew Riedman
May 6, 2016

Using the divisibility test, 3987 and 4365 are both divisible by 9, while 4472 is not. For 4472 to be a solution, it would need to be divisible by gcd(3987,4365)

As seen on the Simpsons, Homer Simpson brilliant "solved" FLT, however this was later proven false by Andrew Wiles.

Dhiraj Kushwaha
May 2, 2015

FERMATS LAST THEOREM......

Bhuwanesh Kumar
Apr 28, 2015

it cannot be true because of Fermat's last theorem. x^n+y^n=z^n if n>2 and n is positive integer have no whole number solution

Chong Eu Meng
Apr 28, 2015

Hint: Use The Even-Odd theory to justify the answer.

Do you mean prove that one side is an even number and the other side is an odd number? If yes, can you show me?

Pi Han Goh - 6 years, 1 month ago

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The RHS is divisible by 4 but the LHS isn't, being the sum of the squares of two odd numbers.

Otto Bretscher - 6 years, 1 month ago
Louis Abraham
Apr 6, 2014

Just check modulo 3 : 3987 mod 3 = 4365 mod 3 = 0 but 4472 mod 3 = -1 therefore 0 would be equal to 1 !

From Fermat's Last Theorem x^12 + y^12 not equal to z^12.. So it's always False.

What is Fermat's Last Theorem..

Mahesh Bongani - 7 years, 2 months ago
Datu Oen
Mar 31, 2014

One possible solution is to determine if the two numbers on the sides of the equations, that is after raising both sides to 12, will be both divisible by a certain number. In this case, I tried 9.

Note that 3987 ( m o d 9 ) 0 3987 \pmod{9} \equiv 0 while 4365 ( m o d 9 ) 0 4365 \pmod {9} \equiv 0 . Thus, 398 7 12 + 436 5 12 ( m o d 9 ) 0 3987^{12} + 4365^{12} \pmod{9} \equiv 0

On the other hand, 4472 ( m o d 9 ) 1 4472 \pmod {9} \equiv -1 . Thus, 447 2 12 ( m o d 9 ) 1 4472^{12} \pmod {9} \equiv 1 . Therefore, they are not equal.

i try to use simple number, like 4, 3 , and 2.

change 12 becomes 3, and 3987 becomes 4 and 4365 becomes 2 (and also try another numbers)

and the result if you change the number is 4,16.

so the conclusion is that the biggest number is the root is the answer

Cuong Phi
Mar 18, 2014

(3987,13)=1 (4365,13)=1 Following Fermat'sTheorem,we have 3987^12=1(mod 13) and 4365^12=1(mod 13) In the other hand, 4472=0(mod 13) So, the following equation is false.

It can be rewritten as follows:

398 7 12 + 436 5 12 = 447 2 12 3987^{12} + 4365^{12} = 4472^{12}

This is the same that

9 12 ( 44 3 12 + 48 5 12 ) = 8 12 1 3 12 4 3 12 9^{12}(443^{12} + 485^{12}) = 8^{12}13^{12}43^{12}

The left hand side is divisible by 3 3 while the right side is not. Therefore the answer is NO .

Thích Thảo
Mar 13, 2014

Let have a look at this equation if it is true (actually it isn’t). √(12&〖3987〗^12+ 〖4365〗^12 )=4472  〖3987〗^12+〖4365〗^12=〖4472〗^12  〖3987〗^12= 〖4472〗^12-〖4365〗^12 * We have: 〖4472〗^12-〖4365〗^12=(〖4472〗^6-〖4365〗^6 )(〖4472〗^6+〖4365〗^6) 〖4472〗^6-〖4365〗^6=(〖4472〗^3-〖4365〗^3 )(〖4472〗^3+〖4365〗^3 ) 〖4472〗^3-〖4365〗^3=(4472-4365)(〖4472〗^2+4472×4365+〖4365〗^2 )=107(〖4472〗^2+4472×4365+〖4365〗^2 ) If * is true, 3987/107 is an integer. Howerver it is not an integer. Thus, the equation is wrong. P/s: I don't know why it doesn't have its origin. So sorry.

Qamar Raj
Mar 13, 2014

No simple bcz both sides are not divisible by 3 so they are not equal also 12 is cut by 12underroot and both sum is not equal to right hand side

aggred with your thincking

Rashid Abdul - 7 years, 2 months ago
Alexander Sludds
Mar 8, 2014

Note, 3 divides 3987 and 4365 but it does not divide 4472. Thus, we have a contradiction.

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