Question

Write the given expression as an algebraic expression in x.

cos(2 cos^−1 x)

Answer 1

too bad the dust is coming
start with
\[\cos(2\theta)=2\cos^2(\theta)-1\]

Answer 2

then replace theta by
\[\cos^{-1}(x)\] and you will get it in one step

Answer 3

\[2x^2-1\] is your answer

Answer 4

thank you!!!!!

Answer 5

yw