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

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

A

`(pi)/(3)`

B

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

C

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

D

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

Text Solution

Verified by Experts

The correct Answer is:
D
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