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!

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- Nov 12th 2009, 03:03 PMl flipboi lLowering Powers - Simplify in terms of cosine
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! - Nov 12th 2009, 03:38 PMpickslides
$\displaystyle \cos^4(x) = (\cos^2(x))^2 = \left(\frac{1+\cos(x)}{2}\right)^2 = \left(\frac{1+\cos(x)}{2}\right) \times \left(\frac{1+\cos(x)}{2}\right)$

Have a look at this.

Table of Trigonometric Identities - Nov 12th 2009, 04:29 PMl flipboi l
- Nov 12th 2009, 04:33 PMpickslides
You are expanding something that does not need to be expanded. You will only end up back at the start.