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If 5cos2theta+2cos^(2)""(theta)/(2)+1=0 ...

If `5cos2theta+2cos^(2)""(theta)/(2)+1=0 and -piltthetaltpi`, then find `theta`.

A

`(pi)/(3)`

B

`(pi)/(3),cos^(-1)(3//5)`

C

`cos^(-1)(3//5)`

D

`pm(pi)/(3),pm(pi-cos^(-1)(3//5))`

Text Solution

Verified by Experts

The correct Answer is:
D
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