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If omega(!=1) is a cube root of unity, ...

If `omega(!=1)` is a cube root of unity, and `(1+omega)^7= A + B omega` . Then (A, B) equals

A

(0,1)

B

(1,1)

C

77

D

64

Text Solution

Verified by Experts

The correct Answer is:
B

We have,
`(1+omega)^(7)=A+Bomega`
`rArr (-omega)^(7)=A+Bomega`
`rArr -omega^(14)=A+Bomega`
`rArr -omega^(2)=A+Bomega rArr A=1,B=1`
Hence, `(A,B)=(1,1)`
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OBJECTIVE RD SHARMA ENGLISH-COMPLEX NUMBERS -Chapter Test
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  19. If Re((z+4)/(2z-1)) = 1/2 then z is represented by a point lying on

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  20. The vertices of a square are z(1),z(2),z(3) and z(4) taken in the anti...

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  21. Let lambda in R . If the origin and the non-real roots of 2z^2+2z+lam...

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