Sinx+sin3x/cosx+cos3x=tg2x

Ответ. sin (x) + (sin (x)) ^2 + (sin (x)) ^3=cos (x) + (cos (x)) ^2 + (cos (x)) ^3; (sin (x) - cos (x)) + (sin (x) - cos (x)) * (sin (x) + cos (x)) + (sin (x) - cos (x)) * ((sin (x)) ^2 + (cos (x)) ^2+sin (x) * cos (x)) = 0;

(sin (x) - cos (x)) * (1+sin (x) + cos (x) + (sin (x)) ^2 + (cos (x)) ^2+sin (x) * cos (x)) = 0; (sin (x) - cos (x)) * (2+sin (x) + cos (x) + sin (x) * cos (x)) = 0; 1). sin (x) - cos (x) = 0; tg (x1) = 1; 2).2+sin (x) + cos (x) + sin (x) * cos (x) = 0; -не имеет решений. Доказательство письмом.