## Calculus (3rd Edition)

$$u=\cos x^{2}\Longrightarrow du =-2x \sin x^2 dx .$$
Recall that $(\cos x)'=-\sin x$. Recall that $(x^n)'=nx^{n-1}$ $$u=\cos x^{2}\Longrightarrow du =-2x \sin x^2 dx .$$