English

Answer the following: If ω is a complex cube root of unity, prove that (1 − ω + ω2)6 +(1 + ω − ω2)6 = 128

Advertisements
Advertisements

Question

Answer the following:

If ω is a complex cube root of unity, prove that (1 − ω + ω2)6 +(1 + ω − ω2)6 = 128

Sum
Advertisements

Solution

ω is the complex cube root of unity

∴ ω3 = 1 and 1 + ω + ω2 = 0

Also, 1 + ω2 = – ω, 1 + ω = – ω2

∴ L.H.S. = (1 – ω + ω2)6 + (1 + ω – ω2)6

= [(1 + ω2) – ω]6 + [(1 + ω) – ω2]6

= (–ω – ω)6 + (–ω2 – ω2)6

= (–2ω)6 + (–2ω2)6

= 64ω6 + 64ω12

= 64(ω3)2 + 64(ω3)4

= 64(1)2 + 64(1)4

= 128

shaalaa.com
  Is there an error in this question or solution?
Chapter 1: Complex Numbers - Miscellaneous Exercise 1.2 [Page 22]

APPEARS IN

RELATED QUESTIONS

If ω is a complex cube root of unity, find the value of `omega + 1/omega`


If ω is a complex cube root of unity, find the value of (1 + ω2)3


If ω is a complex cube root of unity, find the value of (1 - ω - ω2)3 + (1 - ω + ω2)3


If `omega` is a complex cube root of unity, find the value of `(1 + omega)(1 + omega^2)(1 + omega^4)(1 + omega^8)`


If ω is a complex cube root of unity, then prove the following:  (a + b) + (aω + bω2) + (aω2 + bω) = 0.


Find the value of ω–30


If ω is a complex cube root of unity, show that `("a" + "b"ω + "c"ω^2)/("c" + "a"ω + "b"ω^2)` = ω2


If ω is a complex cube root of unity, show that (a + b) + (aω + bω2) + (aω2 + bω) = 0


If ω is a complex cube root of unity, show that (a + b)2 + (aω + bω2)2 + (aω2 + bω)2 = 6ab


If ω is a complex cube root of unity, find the value of (1 + ω2)3


If α and β are the complex cube root of unity, show that α2 + β2 + αβ = 0


If α and β are the complex cube root of unity, show that α4 + β4 + α−1β−1 = 0


If , where α and β are the complex cube-roots of unity, show that xyz = a3 + b3.


Find the equation in cartesian coordinates of the locus of z if |z – 3| = 2


Find the equation in cartesian coordinates of the locus of z if |z + 8| = |z – 4|


Select the correct answer from the given alternatives:

If ω is a complex cube root of unity, then the value of ω99+ ω100 + ω101 is :


If α and β are complex cube roots of unity, prove that (1 − α)(1 − β) (1 − α2)(1 − β2) = 9.


Which of the following is the third root of `(1 + i)/sqrt2`? 


If α, β, γ are the cube roots of p (p < 0), then for any x, y and z, `(xalpha + "y"beta + "z"gamma)/(xbeta + "y"gamma + "z"alpha)` = ______.


Let z = `(1 - isqrt(3))/2`, i = `sqrt(-1)`. Then the value of `21 + (z + 1/z)^3 + (z^2 + 1/z^2) + (z^3 + 1/z^3)^3 + ...... + (z^21 + 1/z^21)^3` is ______.


If the cube roots of the unity are 1, ω and ω2, then the roots of the equation (x – 1)3 + 8 = 0, are ______.


Simplify the following and express in the form a + ib.

`(3i^5 + 2i^7 + i^9)/(i^6 + 2i^8 + 3i^18)`


If w is a complex cube root of unity, show that `((a+bw+cw^2))/(c+aw+bw^2) = w^2`


If w is a complex cube root of unity, show that

`((a + bw + cw^2)) /( c + aw + bw^2 )= w^2`


If w is a complex cube root of unity, show that `((a + bw + cw^2))/(c+aw+bw^2) = w^2`


If w is a complex cube root of unity, show that `((a + bω + cω^2))/(c + aω + bω^2) = ω^2`


If ω is a complex cube-root of unity, then prove the following:

2 + ω −1)3 = −8


If ω is a complex cube-root of unity, then prove the following :

2 + ω − 1)3 = − 8


Find the value of `sqrt(-3) xx sqrt(-6)`.


If w is a complex cube-root of unity, then prove the following

(w2 + w - 1)3 = - 8


If ω is a complex cube-root of unity, then prove the following:

2 + ω − 1)3 = −8


If w is a complex cube-root of unity, then prove the following. 

(w+ w - 1)= - 8


If ω is a complex cube root of unity, show that `((a + bomega + comega^2))/(c + aomega + bomega^2)=omega^2`


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×