$\frac{100-100}{100-100}$ =2

Suppose a problem be given that $\frac{100-100}{100-100}$ =?

Couldn't we solve it in this manner?

$\frac{100-100}{100-100}$

= $\frac{10^2-10^2}{10(10-10)}$

= $\frac{(10+10)(10-10)}{10(10-10)}$

Cancelling 10-10 from the numerator and the denominator we get,

$\frac{10+10}{10}$

= $\frac{20}{10}$

Easy Math Editor

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Math	Appears as
Remember to wrap math in `$` ... `$` or `\[` ... `\]` to ensure proper formatting.
`2 \times 3`	$2 \times 3$
`2^{34}`	$2^{34}$
`a_{i-1}`	$a_{i-1}$
`\frac{2}{3}`	$\frac{2}{3}$
`\sqrt{2}`	$\sqrt{2}$
`\sum_{i=1}^3`	$\sum_{i=1}^3$
`\sin \theta`	$\sin \theta$
`\boxed{123}`	$\boxed{123}$

Comments

You divided by 0 by canceling 10-10, but division by zero is undefined.

حكيم الفيلسوف الضائع - 7 years, 1 month ago

NO YOU CANCELLED (10-10) WHICH IS 0 AND DIVISION BY 0 IS NOT DEFINED

Kushagra Sahni - 7 years, 1 month ago

yeah i was alarmed though

Winston Astillero - 7 years, 1 month ago

Could anyone give me an exact reason as to why division by 0 is undefined........

Anik Mandal - 7 years, 1 month ago

Dividing by 0 is not defined because if you divide 0/0 you can get any value from negative infinity to positive infinity because any number into 0 is 0. and if the numerator is non-zero then no number can satisfy the satisfy the equation

Kushagra Sahni - 7 years, 1 month ago

Thanks for your explanation!

Anik Mandal - 7 years, 1 month ago

If you divide by zero then all numbers become equal and this is thus meaningless, so division by zero is defined to be undefined!! If division by zero was defined then almost entire mathematics would crumble down

Baidehi Chattopadhyay - 7 years, 1 month ago

Well, thanks!

Anik Mandal - 7 years, 1 month ago

@Anik Mandal – Welcome anik :)

Baidehi Chattopadhyay - 7 years, 1 month ago

try to divide a cake made of air. it is like you cannot divide that does not a value or just "nothing".. :)

edjoy rodelas - 7 years, 1 month ago

Wrongggg.... …

Raideep Singh - 7 years, 1 month ago

Dividing zero by zero is not defined...Π™

Raideep Singh - 7 years, 1 month ago

Dear friends why u getting problem in this is because u underestimated or forgot one thing that is

10^2=100. And -10^2 is also 100 so u must take. Both under consideration

Rohit Singh - 7 years ago

10-10 and 10-10 cannot be cancelled cause 0 and 0 cannot be cancelled

Ajay Chandra - 6 years, 2 months ago

10-10=0 in maths /0 is error

Hilmi Haniffa - 6 years, 2 months ago

Is $\lim _{ x->a }{ f(x) } =\frac { 0 }{ 0 }$ defined? If yes, why so?

Manish Dash - 6 years ago

how its possible...?

Mobin Mithun - 5 years, 11 months ago

Diving by zero is the wrong step

Hjalmar Orellana Soto - 5 years, 10 months ago

no.....you cannot divide the numerator and denomenator with zero

Satwik Kumar - 5 years, 10 months ago

no can't do so my dear , because 0 (= 10-10) can't be cancelled from the numerator & denominator , and if we do so then we will get the answer which we ourselves can't explain

Nirmalya Basu - 5 years, 9 months ago

Oh yes you are correct my dear :p

Anik Mandal - 5 years, 9 months ago

Well, 100-100=0, so from the very start you're kinda messing yourself over :P

To the point where no step doesn't divide by zero until (10+10)/10

It took me a while to notice though.

Alex Li - 5 years, 9 months ago

While cancelling, you are assuming that $\dfrac{0}{0} = 1$ which is not the case

Akhil Bansal - 5 years, 8 months ago

why not 100-100/100-100=0/0

anisha mohapatra - 5 years, 3 months ago

Gud

Shrey Fadia - 7 years, 1 month ago

WHAT DO YOU MEAN BY GOOD ? IT IS COMPLETELY WRONG!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

Kushagra Sahni - 7 years, 1 month ago

Hey its wrong i too know it...practically its not possible but theoretically its possible.

Shrey Fadia - 7 years, 1 month ago

@Shrey Fadia – Even theoretically it's impossible since it uses division by zero, which as we all know is undefined.

حكيم الفيلسوف الضائع - 7 years, 1 month ago

@Shrey Fadia – Theoretically possible? IT's using division by zero. the main step is not possible even! how can it be theoretically possible,,lol

Baidehi Chattopadhyay - 7 years, 1 month ago

@Shrey Fadia – NO NOT EVEN THEOROTICALLY. THE STEPS HE PERFORMED ARE ABSOLUTELY WRONG. HE DIVIDE BY 0

Kushagra Sahni - 7 years, 1 month ago

@Shrey Fadia – How can it be theoretically possible, Shrey?????

Anik Mandal - 7 years, 1 month ago

Math	Appears as
Remember to wrap math in `\(` ... `\)` or `\[` ... `\]` to ensure proper formatting.
`2 \times 3`	$2 \times 3$
`2^{34}`	$2^{34}$
`a_{i-1}`	$a_{i-1}$
`\frac{2}{3}`	$\frac{2}{3}$
`\sqrt{2}`	$\sqrt{2}$
`\sum_{i=1}^3`	$\sum_{i=1}^3$
`\sin \theta`	$\sin \theta$
`\boxed{123}`	$\boxed{123}$

100−100100−100\frac{100-100}{100-100}100−100100−100​ =2

Comments

$\frac{100-100}{100-100}$ =2