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If costheta=1/2(x+1/x) then 1/2(x^2+1/x^...

If `costheta=1/2(x+1/x)` then `1/2(x^2+1/x^2)`=

A

`sin 2 theta `

B

`cos 2 theta `

C

`tan 2 theta `

D

`sec 2 theta`

Text Solution

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The correct Answer is:
B
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TARGET PUBLICATION-TRIGONOMETRIC FUNCTIONS OF COMPOUND ANGLES -CRITICAL THINKING
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