cos(2x)cos(x)-sin(2x)*sin(x)=0

Solution for cos(2x)cos(x)-sin(2x)*sin(x)=0 equation:

Simplifying
cos(2x) * cos(x) + -1sin(2x) * sin(x) = 0

Remove parenthesis around (2x)
cos * 2x * cos(x) + -1sin(2x) * sin(x) = 0

Reorder the terms for easier multiplication:
2cos * x * cos * x + -1sin(2x) * sin(x) = 0

Multiply cos * x
2cosx * cos * x + -1sin(2x) * sin(x) = 0

Multiply cosx * cos
2c2o2s2x * x + -1sin(2x) * sin(x) = 0

Multiply c2o2s2x * x
2c2o2s2x2 + -1sin(2x) * sin(x) = 0

Remove parenthesis around (2x)
2c2o2s2x2 + -1ins * 2x * sin(x) = 0

Reorder the terms for easier multiplication:
2c2o2s2x2 + -1 * 2ins * x * ins * x = 0

Multiply -1 * 2
2c2o2s2x2 + -2ins * x * ins * x = 0

Multiply ins * x
2c2o2s2x2 + -2insx * ins * x = 0

Multiply insx * ins
2c2o2s2x2 + -2i2n2s2x * x = 0

Multiply i2n2s2x * x
2c2o2s2x2 + -2i2n2s2x2 = 0

Solving
2c2o2s2x2 + -2i2n2s2x2 = 0

Solving for variable 'c'.

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

Add '2i2n2s2x2' to each side of the equation.
2c2o2s2x2 + -2i2n2s2x2 + 2i2n2s2x2 = 0 + 2i2n2s2x2

Combine like terms: -2i2n2s2x2 + 2i2n2s2x2 = 0
2c2o2s2x2 + 0 = 0 + 2i2n2s2x2
2c2o2s2x2 = 0 + 2i2n2s2x2
Remove the zero:
2c2o2s2x2 = 2i2n2s2x2

Divide each side by '2o2s2x2'.
c2 = i2n2o-2

Simplifying
c2 = i2n2o-2

Take the square root of each side:
c = {-1ino-1, ino-1}