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**1. Homework Statement**

__Simplify__

The problem is either 1+[(cosx)/2]

or

1+[cos (x/2)]

The first one looks unworkable so I'm going with the second...unless any of you see that the first one looks normal....

**2. Homework Equations**

I derived/proved some below....

**3. The Attempt at a Solution**

1+cos(x/2)

cos^2x=2cos(x/2)-1

cos(x/2)= sqrt [(cos^2x+1)/2]

(1+sqrt [(cos^2x+1)/2])^2

[1+cos^2x+1]/2

(2+cos^2x)/2

[2+cos^2x]/2

[(1-2sin^2x)+2]/2

(1/2)-sin^2x

and now I'm obviously stuck...

Thanks for all your help!