Question

cosx-cos2x cos3x-cos4x =0 Solve

Answer 1

The given condition is cos(x) + cos(2x) + cos(3x) + cos(4x) = 0

You can multiply cos * x

cosx + cos(2x) + cos(3x) + cos(4x) = 0

Again you can multiply cos * x

cosx + 2cosx + cos(3x) + cos(4x) = 0

While combining the terms such as cosx + 2cosx = 3cosx

Finally, we get 10cosx = 0