Download the app

Questions  

If cosθ=12x+1x then 12x2+1x2 is equal to

a
sin 2θ
b
cos 2θ
c
tan 2θ
d
None of these

detailed solution

Correct option is B

Given that, cos⁡θ=12x+1x⇒x+1x=2cos⁡θ----iWe know that,x2+1x2=x+1x2−2=(2cos⁡θ)2−2=4cos2⁡θ−2=2cos⁡2θ∴12x2+1x2=12×2cos⁡2θ=cos⁡2θ

Talk to our academic expert!

+91

Are you a Sri Chaitanya student?


Similar Questions

3cosec20sec20 is equal to


phone icon
whats app icon