Himpunan penyelesaiain sin 5x sin x = sin 6x sin 2x

-2sin a sin b = cos (a+b) - cos (a-b)

sin 5x sin x = sin 6x sin 2x

-2(sin 5x sin x) = -2(sin 6x sin 2x)

cos (5x + x) - cos (5x - x) = cos (6x + 2x) - cos (6x - 2x) 

cos (6x) - cos (4x) = cos (8x) - cos (4x) 

cos (6x) = cos (8x)

aturan 1; 

6x = 8x + k.360

2x = k.360

x = k.180 , jadi x = 0; 180; 360

aturan 2; 

6x = - 8x + k.360

14x = k.360

x = k.(180/7) , jadi x = 0; 1(180/7); 2(180/7); 3(180/7); 4(180/7); 5(180/7); 6(180/7); 7(180/7); 8(180/7); 9(180/7); 10(180/7); 11(180/7); 12(180/7); 13(180/7); 14(180/7)