sin²2x = sin2x
sin²2x - sin2x = 0
设 y = sin2x
y(y - 1) = 0
y1 = 0
y2 = 1
2x1 = kπ
x1 = kπ/2
2x2 = 2kπ + π/2
x2 = kπ + π/4
即:
x1 = kπ/2 ,k ∈ Z
x2 = kπ + π/4,k ∈ Z
sin²2x = sin2x
sin²2x - sin2x = 0
设 y = sin2x
y(y - 1) = 0
y1 = 0
y2 = 1
2x1 = kπ
x1 = kπ/2
2x2 = 2kπ + π/2
x2 = kπ + π/4
即:
x1 = kπ/2 ,k ∈ Z
x2 = kπ + π/4,k ∈ Z