Cos(2x)+cos(x)=-1

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Solution for Cos(2x)+cos(x)=-1 equation: 


Simplifying
Cos(2x) + cos(x) = -1

Remove parenthesis around (2x)
osC * 2x + cos(x) = -1

Reorder the terms for easier multiplication:
2osC * x + cos(x) = -1

Multiply osC * x
2osxC + cos(x) = -1

Multiply cos * x
2osxC + cosx = -1

Reorder the terms:
cosx + 2osxC = -1

Solving
cosx + 2osxC = -1

Solving for variable 'c'.

Move all terms containing c to the left, all other terms to the right.

Add '-2osxC' to each side of the equation.
cosx + 2osxC + -2osxC = -1 + -2osxC

Combine like terms: 2osxC + -2osxC = 0
cosx + 0 = -1 + -2osxC
cosx = -1 + -2osxC

Divide each side by 'osx'.
c = -1o-1s-1x-1 + -2C

Simplifying
c = -1o-1s-1x-1 + -2C

Reorder the terms:
c = -2C + -1o-1s-1x-1

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