Решить sin^2 +sin x cos x-2 cos^2 x=0

Sin^2x +Sin x cos x-2 cos^2 x=0; / cos^2 x ≠ 0;
tg^2 x + tg x - 2 = 0;
 D = 1 + 8 = 9 = 3^2;
 tg x = (- 1 + 3) / 2= 1;
 tg x = pi/4 + pi*k ; k-Z.

tg x = ( - 1 - 3) / 2= - 2;
 x = - arctg2 + pi*k; k-Z