1.

If \[\frac{1}{x}+x=2\cos \theta ,\] then \[{{x}^{n}}+\frac{1}{{{x}^{n}}}\] is equal to [UPSEAT 2001]

A. \[2\cos n\theta \]
B. \[2\sin n\theta \]
C. \[\cos n\,\theta \]
D. \[\sin \,n\theta \]
Answer» B. \[2\sin n\theta \]


Discussion

No Comment Found