Toán học - Lớp 11 - 2019-09-09 20:37:20 3) sin^2x - 3 . sinx cosx + 1 = 0 4) sin^2x - (√3 - 1 ) . sinx cosx - √3cos^2x = 0 5) cos x/4 - √8 . cos x/8 = 0 6) sin^2 2x - cos^2 x + 3/4 = 0 7) sinx - 1/8inx = sin^2x + 1/sin^2x 8) 9 - 4 . sin^2x - 8cos^2 x/2 = 0