sin 4x − cos 2x = 0
2sin 2x cos 2x − cos 2x = 0
cos2x (2sin 2x - 1) = 0
EITHER
cos 2x = 0
OR
sin 2x = 1/2
Or, in decimal form:
x = 0.26, 0.79, 1.31, 2.36, 3.40, 3.93, 4.45, 5.50.
The graph of y = sin 4x − cos 2x is of the form: