TỔNG HỢP LƯỢNG GIÁC HAY 12- s inx + sin x + sin x + sin x = cos x + cos x + cos x + cos x cos 3x(2 cos x + 1) = 3- cos x(cos x − 1) = 2(1 + s inx) s inx + cos x 45678910- 17π − x)cos2 x = 16 cos x 2sin x − sin x + s inx + cos x − = sin x(2 cos x + 1) + = cos3 x + cos2 x − 3cos x cos x cos x + s inx = cos8 x 9sin x + cos x − 3sin x + cos2 x = 8cos3 x + sin 2 x + 2cos( cos x + cos x − 3cos2 x = sin x + π cos 3x cos x + 3(1 + sin x) = 3cos (2 x + )