Hello,
Can someone please show me all the algebraic steps for simplifying cos^4x?
The problem should be
cos^4x = ((1+cos2x)/2)((1+cos2x)/2)
thanks!
$\displaystyle \cos^4(x) = (\cos^2(x))^2 = \left(\frac{1+\cos(x)}{2}\right)^2 = \left(\frac{1+\cos(x)}{2}\right) \times \left(\frac{1+\cos(x)}{2}\right)$
Have a look at this.
Table of Trigonometric Identities