u(x)=x² du/dx=2x
导数=√(1+(x²)²·2x
v(x)=x² dv/dx=2x
导数=-e^(x²)·2x
u(x)=cosx du/dx=-sinx
v(x)=sinx dv/dx=cosx
导数=cos(πcosx)·-sinx-cos(πsinx)·cosx
