6sin^2x+5sin(p/2-x)-2=0

6 sin^2 x + 5 sin (p/2 - x)  - 2 = 0;  sin^2 x = 1 - cos^2 x ; sin (p/2 - x ) = cos x;  6(1 - cos^2 x) + 5 cos x - 2 = 0; 6 - 6 cos^2 x + 5 cos x - 2 = 0; 6 cos^2 x - 5 cos x - 4 = 0;  D = 25 + 96 = 121= 11^2;  cos x = 4/3 > 1; ∅;  cos x = - 1/2;  x = + - p/3  + 2pk;k-Z