If x+1x=2cos⁡θ, then for any integraleger n,xn+1xn= | Mathematics | SolveeIt | Solveeit

Today, August 19

Question

If x+1x=2cos⁡θ, then for any integer n,xn+1xn=

A

(A) 2 cos nθ

B

(B) 2 sin nθ

C

(C) 2i cos nθ

D

(D) 2i sin nθ

Answer

(A) 2 cos nθ

Explanation

Solution

Explanation:
x+1x=2cos⁡θ Let x=cos⁡θ+1sin⁡θ1x=cos⁡θ−1sin⁡θ Thus xn+1xn=2cos⁡nθ