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If x+(1)/(x)=2cos alpha then x^(n)+(1)/(...

If `x+(1)/(x)=2cos alpha` then `x^(n)+(1)/(x^(n))`=

A

`2^(n) cos alpha`

B

`2^(n) cos n alpha`

C

`2 i sin n alpha`

D

`2 cos n alpha`

Text Solution

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The correct Answer is:
D
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HIMALAYA PUBLICATION-COMPLEX NUMBERS-QUESTION BANK
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  12. The conjugate of the complex number (1 + i)^(2)/(1-i) is

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