Giải phương trình lượng giác: a) sin5x + sin3x = 0; b) cot2x.cot3x = 1

a, sin5x+sin3x=0
b, cot2x.cot3x=1
c, (cot x/3 -1) (cot x/2+1)=0
d, (3tanx+√ 3) (2sinx-1)=0
e, tan(x-30°) cos(2x-150°)=0
f, tan(x-π/4)+cot2x=0
g, tanx-sin2x=0
h, cotx+tanx=-2
i, sin5x.sin7x=cos3x.cos5x
k, cosx-cos2x+cos3x=0
j, cos4x.cos6x=1
m, 1-cotx/1-tanx=2cosx