Question

Интеграл от cosx^2dx

Answer 1

$\int (cosx)^2dx=\int \frac{1-cos2x}{2}dx=\frac{1}{2}\int dx-\frac{1}{2}\int cos2x\, dx=\\\\=\frac{1}{2}x-\frac{1}{2}\cdot \frac{1}{2}sin2x+C=\frac{x}{2}-\frac{sin2x}{4}+C$