Ксения6 лет назад
sin (5 * x) + sin x + 2 * sin^2 x = 1;
Упростим уравнение.
2 * sin ((5 * x + x)/2) * cos ((5 * x - x)/2) + 2 * sin^2 x = 1;
2 * sin (6 * x/2) * cos (4 * x/2) + 2 * sin^2 x = 1;
2 * sin (3 * x) * cos (2 * x) + 2 * sin^2 x - 1 = 0;
2 * sin (3 * x) * cos (2 * x) + 2 * sin^2 x - cos^2 x - sin^2 x = 0;
2 * sin (3 * x) * cos (2 * x) + sin^2 x - cos^2 x = 0;
2 * sin (3 * x) * cos (2 * x) - (cos^2 x - sin^2 x) = 0;
2 * sin (3 * x) * cos (2 * x) - cos (2 * x) = 0;
cos (2 * x) * (2 * sin (3 * x) - 1) = 0;
1) cos (2 * x) = 0;
2 * x = п/2 + п * n, n ∈ Z;
x = п/4 + п/2 * n, n ∈ Z;
2) 2 * sin (3 * x) = 1;
sin (3 * x) = 1/2;
3 * x = (-1)^n * п/6 + п * n, n ∈ Z;
x = (-1)^n * п/18 + п/3 * n, n ∈ Z.