Seemingly Random Polynomial

Algebra Level 4

x 63 + x 44 + x 37 + x 31 + x 26 + x 9 + 6 \large x^{63} + x^{44} + x^{37} + x^{31} + x^{26} + x^9 + 6

If x x satisfies the equation ( x + 1 x ) 2 = 3 \left(x + \dfrac1x\right)^2 = 3 , then find the value of the expression above.


The answer is 6.

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13 solutions

Sanjeet Raria
Dec 26, 2014

We have, ( x + 1 x ) 2 = 3 (x+\frac{1}{x})^2=3 ( x + 1 x ) = 3 \Rightarrow (x+\frac{1}{x})=√3 ( x 3 + 1 x 3 ) = 0 \Rightarrow (x^3+\frac{1}{x^3})=0

Further it can be seen that for every n N n \in N , ( x 3 n + 1 x 3 n ) = 0 ( W h y ) (x^{3n}+\frac{1}{x^{3n}})=0 \space (Why)

Now our required expression is, x 37 + x 31 + x 44 + x 26 + x 63 + x 9 + 6 x^{37}+ x^{31}+ x^{44}+ x^{26}+ x^{63}+ x^{9}+6 = x 34 ( x 3 + 1 x 3 ) + x 35 ( x 9 + 1 x 9 ) + x 36 ( x 27 + 1 x 27 ) + 6 =x^{34}(x^3+\frac{1}{x^3})+ x^{35}(x^9+\frac{1}{x^9})+ x^{36}(x^{27}+\frac{1}{x^{27}})+6 = x 34 ( 0 ) + x 35 ( 0 ) + x 36 ( 0 ) + 6 = 6 = x^{34}(0)+ x^{35}(0)+ x^{36}(0)+6=\boxed{6}

Any other solutions are welcomed for the sake of variety.

Nice solution. Another way I did is ::

x 2 + 1 x 2 + 2 = 3 x^2+\frac{1}{x^2}+2=3

x 2 + 1 x 2 = 1 \implies x^2+\dfrac{1}{x^2}=1

x 2 = ω o r x 2 = ω 2 \implies x^2=-\omega \ or \ x^2=-\omega^2 ω \omega being a cube root of unity.

So using the properties of ω \omega , Every term of the given expression is cancelled out except 6 6 . S0 6 \boxed{6} is the value of the given expression. @Sanjeet Raria

Sandeep Bhardwaj - 6 years, 5 months ago

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done the same way.

Trishit Chandra - 6 years, 3 months ago

Done the same way

Arkin Dharawat - 5 years, 9 months ago

even i did it in the same way :)

Devendra Veerelli - 6 years, 5 months ago

y n + 1 y n = 2 c o s n x y^{n} + \dfrac{1}{y^{n}} = 2cosnx , ( Since y = e i x y={ e }^{ ix } )

c o s x = 3 2 cosx = \dfrac{\sqrt{3}}{2}

then as @Jake Lai did

U Z - 6 years, 5 months ago

In response to Sanjeet Raira: can you explain the step how x^3+1/x^3=0 from previous step?

Sridhar Muruganandham - 6 years, 5 months ago

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x 2 + 1 x 2 = 1 x^2 + \dfrac{1}{x^2} = 1

x 2 + 1 x 2 1 = 0 x^2 + \dfrac{1}{x^2} - 1 = 0

( x + 1 x ) ( x 2 + 1 x 2 1 ) = 0 (x + \dfrac{1}{x})( x^2 + \dfrac{1}{x^2} - 1) = 0

x 3 + 1 x 3 = 0 x^3 + \dfrac{1}{x^3} = 0

This will help us,

take the power 37 and 31 , 37 + 31 2 = 34 \dfrac{37 + 31}{2} = 34

x 37 + x 31 = x 34 ( x 3 + 1 x 3 ) x^{37} + x^{31} = x^{34}( x^3 + \dfrac{1}{x^3})

now take power 44 and 26, 44 + 26 2 = 35 \dfrac{44 + 26}{2} = 35

x 44 + x 26 = x 35 ( x 9 + 1 x 9 ) x^{44} + x^{26} = x^{35}(x^9 + \dfrac{1}{x^9}) (apply a 3 + b 3 a^3 + b^3 )

take 63 and 9 , see a pattern of power continues , first it was 34 then 35 so we can take 36 , or once again we can apply the same procedure to find which power to be taken common, 63 + 9 2 = 36 \dfrac{63 + 9}{2} = 36

or x 3 n + 1 x 3 n = 0 x^{3n} + \dfrac{1}{x^{3n}} = 0 (as x 3 + 1 x 3 = 0 x^3 + \dfrac{1}{x^3} = 0 )

U Z - 6 years, 5 months ago

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Thanks for your answer @Megh Choksi, why are you multiplying (x+1/x)?

Sridhar Muruganandham - 6 years, 5 months ago

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@Sridhar Muruganandham For making x 3 + 1 x 3 x^3 + \dfrac{1}{x^3} , sanjeet raria sir cubed both the sides to get it zero

U Z - 6 years, 5 months ago

( x + 1 x ) : (x+\frac{1}{x}): A form you like. @brian charlesworth

Sanjeet Raria - 6 years, 5 months ago

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Nice problem and solution, Sanjeet. My approach was the same as Sujoy's, once I observed that x 4 x 2 + 1 x^{4} - x^{2} + 1 was a factor x 6 + 1 x^{6} + 1 .

Brian Charlesworth - 6 years, 5 months ago

I ALSO DID LIKE THIS!!

Aakash Khandelwal - 5 years, 10 months ago

I agree that x^3 + 1/x^3 is 0, however, would not x^6 + 1/x^6 = -2? That is at least what I get when squaring the first expression x^3 + 1/x^3

Adam Pet - 5 years, 10 months ago

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i am also confused about that

but i think the expression should be like this

when x 3 + 1 x 3 = 0 x^3 + \frac{1}{x^3} = 0 then x 3 n + 1 x 3 n = 0 x^{3^n} + \frac{1}{x^{3^n}} = 0 too, provided n N n \in \mathbb N }

which applies to only x 3 + 1 x 3 x^3 + \frac{1}{x^3} , x 9 + 1 x 9 x^9 + \frac{1}{x^9} , x 27 + 1 x 27 x^{27} + \frac{1}{x^{27}} and so on.

using the similar calculation to form x 3 + 1 x 3 x^3 + \frac{1}{x^3} from x + 1 x x + \frac{1}{x} and x 2 1 + 1 x 2 x^2 - 1 + \frac{1}{x^2} , we could have :

( x 3 + 1 x 3 ) ( x 6 1 + 1 x 6 ) (x^3 + \frac{1}{x^3}) \cdot (x^6 -1 + \frac{1}{x^6}) = x 9 + 1 x 9 x^9 + \frac{1}{x^9}

hence x 9 + 1 x 9 x^9 + \frac{1}{x^9} = 0 too

x 27 + 1 x 27 x^{27} + \frac{1}{x^{27}} and higher would have a similar way

correct me if there were mistakes

Kevin Erdiza - 5 years, 9 months ago

x^3+1/x^3 = 0 suppose for n<=k, x^3n+1/x^3n = 0 now, (x^3k+1/x^3k)(x^3+1/x^3) = 0 = x^3(k+1)+x^3(k-1)+1/x^3(k-1)+1/x^3(k+1) now, x^3(k-1)+1/x^3(k-1) = 0 by our inductive step so, x^3(k+1)+1/x^3(k+1) = 0 this proves the induction

Joey Chemis - 6 years, 5 months ago

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What about x^6+1/x^6, x^12+1/x^12.....????

Niaz Ghumro - 6 years, 5 months ago

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x^6+1/x^6 = 0 because of my proof above same for x^12+1/x^12...

Joey Chemis - 6 years, 5 months ago

do you intentionally put the answer "6.00" to confuse members (liked this)?

Gautam Sharma - 6 years, 4 months ago

same method!

Huân Lê Quang - 5 years, 10 months ago

Slight mistake in your rule x^(3n)+x^(-3n)=0 this works for n=3,9 but doesn't work for n=2, which equals -2. Not sure what the exact rule is for which n the identity works for but it does not work for all natural n.

Thomas Fry - 5 years, 1 month ago

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Exactly.. This mistake also puzzled me for few minutes...

Prokash Shakkhar - 4 years, 9 months ago

Nice Problem ! :D

Keshav Tiwari - 6 years, 5 months ago

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Thank you.

Sanjeet Raria - 6 years, 5 months ago

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I am getting a different answer by Wolfram Alpha. Please see a comment below.

Dawar Husain - 6 years, 5 months ago

x^3n+1/x^3n=0 for all natural number is incorrect when x^6+1/x^6, x^12+1/x^12....etc. it would be correct only 3n=3,9,27,81,.... Please rectify me if I may be wrong.

Niaz Ghumro - 6 years, 5 months ago

Exactly how I solved it!

M Dub - 5 years, 10 months ago

Wonderful Solution!

Cleres Cupertino - 5 years, 10 months ago

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Thank you.

Sanjeet Raria - 5 years, 10 months ago

how did you do the 3rd step in the first line

abhishek alva - 4 years, 11 months ago

Nice solution sir..................really a elegant one............But sir i was having a doubt in buying resnick,halliday and walker book............actually there are so many editions coming that i am a bit confused which one to buy even resnick,halliday and krane is also coming ...............sir please help and if possible send me a link......i would be thankful to you...........

Abhisek Mohanty - 4 years, 11 months ago

( x + 1 / x ) 2 = 3 , ( x + 1 / x ) 3 = 3 3 . 3 3 = ( x + 1 / x ) 3 = ( x 3 + 1 / x 3 ) + 3 x 1 / x ( x + 1 / x ) = x 3 + 1 / x 3 + 3 3 . x 3 + 1 / x 3 = 0. L e t x = y 3 , y 3 + 1 / y 3 = 0. , x 9 + 1 / x 9 = 0. S i m i l a r l y , x 27 + 1 / x 27 = 0 x 3 n + 1 / x 3 n 0 f o r e v e r y n N . x 3 n + 1 / x 3 n = 0 f o r e v e r y n N . (x+1/x)^2=3,~~\implies~(x+1/x)^3=3\sqrt3.\\ \therefore ~3\sqrt3=(x+1/x)^3\\ =(x^3+1/x^3)+3*x*1/x*(x+1/x)\\ =x^3+1/x^3+3\sqrt3.\\ \implies~x^3+1/x^3=0.\\ Let~x=y^3,~~\therefore~y^3+1/y^3=0.\\ \implies~,~~x^9+1/x^9=0.\\ Similarly~,~~x^{27}+1/x^{27}=0\\ \color{#3D99F6}{~x^{3n}+1/x^{3n}\neq 0 ~for~every~n\in N.}\\ \color{#D61F06}{~x^{3^n}+1/x^{3^n} ~=~ 0 ~for~every~n\in N.}\\

Niranjan Khanderia - 2 years, 9 months ago
Sujoy Roy
Dec 26, 2014

( x 2 + 1 x 2 ) 2 = 3 (x^2+\frac{1}{x^2})^2=3

or, x 4 x 2 + 1 = 0 x^4-x^2+1=0

or, ( x 2 + 1 ) ( x 4 x 2 + 1 ) = 0 (x^2+1)(x^4-x^2+1)=0

or, x 6 + 1 = 0 x^6+1=0 or, x 6 = 1 x^6=-1

So, x 63 + x 44 + x 37 + x 31 + x 26 + x 9 + 6 x^{63}+x^{44}+x^{37}+x^{31}+x^{26}+x^{9}+6

= x 3 x 2 + x x + x 2 x 3 + 6 = 6 =x^{3}-x^{2}+x-x+x^{2}-x^{3}+6=\boxed{6}

Used complex number(De- Moivre's theorem) to solve, Method of solving is quite similar.

Prakash Chandra Rai - 6 years, 5 months ago

Nice solution.

Sanjeet Raria - 6 years, 5 months ago

Awesome. I aappreciate your solution. I really liked the way you did this.

Ninad Akolekar - 6 years, 5 months ago

good solution simple but not complicated

Nguyễn Bình Nguyên - 6 years, 5 months ago

same method (Y)

KiXiao Cheng Leong - 5 years, 7 months ago

I have up voted as the best and simple direct solution.

Niranjan Khanderia - 3 years, 4 months ago
Jake Lai
Dec 26, 2014

Recall that cos θ = e i θ + e i θ 2 \cos \theta = \frac{e^{i\theta}+e^{-i\theta}}{2} . Substituting in x = e i θ x = e^{i\theta} gives

cos θ = 3 2 \cos \theta = \frac{\sqrt{3}}{2}

Since the ratio of the adjacent side to the hypotenuse in a 30-60-90 triangle from the angle π / 6 \pi/6 is 3 2 \frac{\sqrt{3}}{2} , we can conclude

x = e i θ = e i π / 6 = ( 1 ) 1 / 6 x = e^{i\theta} = e^{i\pi/6} = (-1)^{1/6}

It can be easily seen that x 6 m + n = ( 1 ) m x n x^{6m+n} = (-1)^{m}x^{n} . Hence, our given expression is equal to

x 3 x 2 + x x + x 2 x 3 + 6 = 6 x^{3}-x^{2}+x-x+x^{2}-x^{3}+6 = \boxed{6}

Same , y n + 1 y n = 2 c o s n x y^{n} + \dfrac{1}{y^{n}} = 2cosnx , ( Since y = e i x y={ e }^{ ix } ) +1

U Z - 6 years, 5 months ago

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Much appreciated :3

Jake Lai - 6 years, 5 months ago
Tan Kiat
Dec 27, 2014

( x + 1 x ) 2 = 3 (x + \dfrac{1}{x})^2 = 3

= > x 2 + 1 x 2 = 1 => x^2 + \dfrac{1}{x^2} = 1

= > x n = x n 2 x n 4 = > x^n = x^{n-2} - x^{n-4} by multiplying x n 2 x^{n-2} on both sides

Hence, the above also yields = > x n 2 = x n 4 x n 6 = > x^{n-2} = x^{n-4} - x^{n-6} , where substituting it back in to the previous equation yields

x n = x n 6 x^n = -x^{n-6}

Using this, the expression :

x 63 + x 44 + x 37 + x 31 + x 26 + x 9 + 6 x^{63} + x^{44} + x^{37} + x^{31} + x^{26} + x^{9} + 6

= x 3 x 2 + x x + x 2 x 3 + 6 = x^{3} - x^{2} + x - x + x^2 - x^3 + 6

= 6 = \boxed{6}

Huân Lê Quang
Aug 5, 2015

Obviously, From the problem, we have: ( x + 1 x ) 2 = x 2 + 1 x 2 + 2 = 3 x 2 + 1 x 2 = 1 \left( x+\frac { 1 }{ x } \right) ^{ 2 }={ x }^{ 2 }+\frac { 1 }{ { x }^{ 2 } } +2=3\Rightarrow { x }^{ 2 }+\frac { 1 }{ { x }^{ 2 } } =1

Therefore: x 3 + 1 x 3 = ( x + 1 x ) ( x 2 + 1 x 2 1 ) = ( x + 1 x ) 0 = 0 { x }^{ 3 }+\frac { 1 }{ { x }^{ 3 } } =\left( x+\frac { 1 }{ x } \right) \left( { x }^{ 2 }+\frac { 1 }{ { x }^{ 2 } } -1 \right) =\left( x+\frac { 1 }{ x } \right) \cdot 0=0 . Furthermore, we can prove by induction:

( x ( 3 n ) + 1 x ( 3 n ) ) = 0 \left( { x }^{ \left( { 3 }^{ n } \right) }+\frac { 1 }{ { x }^{ \left( { 3 }^{ n } \right) } } \right) =0 , when ( x + 1 x ) 2 = 3 \left( x+\frac { 1 }{ x } \right) ^{ 2 }=3 and n N n\in N

Now, our expression is: x 63 + x 44 + x 37 + x 31 + x 26 + x 9 + 6 { x }^{ 63 }+{ x }^{ 44 }+{ x }^{ 37 }+{ x }^{ 31 }+{ x }^{ 26 }+{ x }^{ 9 }+6 = x 35 ( x 9 + 1 x 9 ) + x 36 ( x 27 + 1 x 27 ) + x 34 ( x 3 + 1 x 3 ) + 6 ={ x }^{ 35 }\left( { x }^{ 9 }+\frac { 1 }{ { x }^{ 9 } } \right) +{ x }^{ 36 }\left( { x }^{ 27 }+\frac { 1 }{ { x }^{ 27 } } \right) +{ x }^{ 34 }\left( { x }^{ 3 }+\frac { 1 }{ { x }^{ 3 } } \right) +6 = 0 + 0 + 0 + 6 =0+0+0+6 = 6 =6

Moderator note:

Good observation with the inductive step.

Do you know how to state the value of x x in a simple manner?

On mobile i can't see last digit 6,so i made error,please shorten it. Display smaller letters to fit on any screen.

Nikola Djuric - 4 years, 4 months ago
Rindell Mabunga
Dec 27, 2014

This will be easy if we put this on the complex plane.

( x + 1 x ) 2 = 3 (x + \frac{1}{x})^2 = 3

x 2 + 2 + 1 x 2 = 3 x^2 + 2 + \frac{1}{x^2} = 3

x 4 x 2 + 1 = 0 x^4 - x^2 + 1 = 0

The roots will be c i s ( Π 6 cis(\frac{\Pi }{6} ), c i s ( 5 Π 6 cis(\frac{5\Pi}{6} ), c i s ( 7 Π 6 cis(\frac{7\Pi}{6} ), and c i s ( 11 Π 6 cis(\frac{11\Pi}{6} ).

Then substitute to the expression, (let's use c i s ( Π 6 cis(\frac{\Pi }{6} ))

x 63 + x 44 + x 37 + x 31 + x 26 + x 9 + 6 x^{63} + x^{44} + x^{37} + x^{31} + x^{26} + x^9 + 6

= c i s ( 63 × Π 6 ) + c i s ( 44 × Π 6 ) + c i s ( 37 × Π 6 ) + c i s ( 31 × Π 6 ) + c i s ( 26 × Π 6 ) + c i s ( 9 × Π 6 ) + 6 = cis(63 \times \frac{\Pi }{6}) + cis(44 \times \frac{\Pi }{6}) + cis(37 \times \frac{\Pi }{6}) + cis(31 \times \frac{\Pi }{6}) + cis(26 \times \frac{\Pi }{6}) + cis(9 \times \frac{\Pi }{6}) + 6

= c i s ( 21 Π 2 ) + c i s ( 22 Π 3 ) + c i s ( 37 Π 6 ) + c i s ( 31 Π 6 ) + c i s ( 13 Π 3 ) + c i s ( 3 Π 2 ) + 6 = cis(\frac{21\Pi }{2}) + cis(\frac{22\Pi }{3}) + cis(\frac{37\Pi }{6}) + cis(\frac{31\Pi }{6}) + cis(\frac{13\Pi }{3}) + cis(\frac{3\Pi }{2}) + 6

= c i s ( 1 Π 2 ) + c i s ( 2 Π 3 ) + c i s ( 1 Π 6 ) + c i s ( 1 Π 6 ) + c i s ( 1 Π 3 ) + c i s ( 1 Π 2 ) + 6 = cis(\frac{1\Pi }{2}) + cis(\frac{-2\Pi }{3}) + cis(\frac{1\Pi }{6}) + cis(\frac{-1\Pi }{6}) + cis(\frac{1\Pi }{3}) + cis(\frac{-1\Pi }{2}) + 6

= [ c o s ( 1 Π 2 ) + c o s ( 2 Π 3 ) + c o s ( 1 Π 6 ) + c o s ( 1 Π 6 ) + c o s ( 1 Π 3 ) + c o s ( 1 Π 2 ) + 6 ] + ι [ s i n ( 1 Π 2 ) + s i n ( 2 Π 3 ) + s i n ( 1 Π 6 ) + s i n ( 1 Π 6 ) + s i n ( 1 Π 3 ) + s i n ( 1 Π 2 ) ] = [cos(\frac{1\Pi }{2}) + cos(\frac{-2\Pi }{3}) + cos(\frac{1\Pi }{6}) + cos(\frac{-1\Pi }{6}) + cos(\frac{1\Pi }{3}) + cos(\frac{-1\Pi }{2}) + 6] + \iota[sin(\frac{1\Pi }{2}) + sin(\frac{-2\Pi }{3}) + sin(\frac{1\Pi }{6}) + sin(\frac{-1\Pi }{6}) + sin(\frac{1\Pi }{3}) + sin(\frac{-1\Pi }{2})]

= 0 = 0

Using the other roots will also lead to 0 .

Vishnu Kadiri
Sep 8, 2016

x 2 + 1 x 2 = 1. x 4 = x 2 1..... ( A ) . x 8 = x 4 2 x 2 + 1 = x 2 . . . . . ( B ) . x 6 = 1...... ( C ) . x 12 = 1.... ( D ) , a n d x 3 = i . . . . . . ( E ) B y ( D ) a n d ( E ) x 63 = ( x 12 ) 5 x 3 = i B y ( D ) a n d ( E ) x 44 = ( x 12 ) 3 x 8 = x 2 B y ( D ) x 37 = ( x 12 ) 3 x = x B y ( D ) a n d ( C ) x 31 = ( x 12 ) 2 x 6 x = x ( D ) x 26 = ( x 12 ) 2 x 2 = x 2 B y ( C ) a n d ( E ) x 9 = x 6 x 3 = i x 63 + x 44 + x 37 + x 31 + x 26 + x 9 + 6 = i + x 2 + x x + x 2 i + 6 = 6 x^2+\dfrac 1 {x^2}=1.~~~~~~~~{\color{#3D99F6}{\implies~x^4=x^2-1.....(A)}}.~~~~~~~~\therefore~x^8=x^4-2x^2+1= - x^2.....(B).\\ \therefore~x^6= - 1......(C).~~~~~~~~~~~{\color{#3D99F6}{\implies~x^{12}=1....(D)}},~~~~~~~~~~~and~~~~~~~~x^3= i......(E)\\ {\color{#3D99F6}{By~(D)~and~(E)~~x^{63}=(x^{12})^5*x^3= i } }~~~~~~~~ By~(D)~and~(E)~~x^{44}=(x^{12})^3*x^8= - x^2 \\ By~(D)~~~x^{37}=(x^{12})^3*x= x~~~~~~~~~~~\color{#3D99F6}{By~(D)~and~(C)~~x^{31}=(x^{12})^2*x^6x= - x}\\ {\color{#3D99F6}{~(D)~~~x^{26}=(x^{12})^2*x^2= x^2}}~~~~~~~~~By~(C)~and~(E)~~x^9=x^{6}*x^3= - i\\ \therefore~ x^{63} + x^{44} + x^{37} + x^{31} + x^{26} + x^{9} + 6\\ =~~~i~~~~+ - x^2 ~~+~~x~~~ - ~x ~~~+ x^2~~- i~~+~~6=\color{#D61F06}{6}

Better still:
( x + 1 / x ) 2 = 3 x 2 + 1 / x 2 = 1 , o r x 4 = x 2 1 = 0 x 6 = x 4 x 2 = x 2 1 x 2 = 1 , S o x 6 = 1 x 3 = i . R e d u c i n g a l l e x p o n e n t s u s i n g x 6 a n d x 3 E x p = x 6 10 x 3 + x 6 7 x 2 + x 6 6 x + x 6 5 x + x 6 4 x 2 + x 6 x 3 + 6 E x p . = 1 i 1 x 2 + 1 x 1 x + 1 x 2 1 i + 6 = 6. (x+1/x)^2=3~~\implies~x^2+1/x^2=1,~~or~~x^4=x^2-1=0\\ \therefore~x^6=x^4-x^2=x^2-1-x^2=-1,\\ \Large So~~x^6=-1~~~~~~~~x^3= i.\\ Reducing~all~exponents~using~x^6~and~x^3\\ Exp=x^{6*10}*x^3~+~x^{6*7}*x^2~+~x^{6*6}*x~+~x^{6*5}*x~ +~x^{6*4}*x^2~+~x^6*x^3~ +~6\\ Exp. \huge ={\color{#EC7300}{1*i}~~-~~\color{#3D99F6}{1*x^2}~~ \color{#20A900}{+~~1*x~~-~~1*x}~~+~~\color{#3D99F6}{1*x^2}~~-~~\color{#EC7300}{1*i} }~~+~~6~=~6.

Niranjan Khanderia - 2 years, 9 months ago

evaluate x^63+x^44+x^37+x^31+x^26+x^9+6, (x+1/x)^2=3 (wolframalpha substitution case)

x^63+x^44+x^37+x^31+x^26+x^9+6=6

Try to find roots take those comples roota in euler form....put it in equation

Subh Mandal
Sep 7, 2016

Solve to get x=iw,Substitute x=iw in eq to get 6 where w is cube root of unity.

Md Zuhair
Aug 11, 2016

Here we get for ( x + 1 / x ) 2 = 3 \Large (x +1/x)^2 = 3 we get x 2 \Large {x^2} = - ω \Large {\omega} [where ω \omega is the cube root of unity ]

By further Solving x 63 + x 44 + x 37 + x 31 + x 26 + x 9 + 6 \large x^{63} + x^{44} + x^{37} + x^{31} + x^{26} + x^9 + 6

And putting the values care fully we get all cut down except 6. Hence Ans = 6 6

x^12=1, so just reduce the exponents.

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