复合函数应该用链式法则求导：若y=g(u),u=f(x),则dy/dx=dy/du*du/dxy=sin^5xdy/dx=dsin^5x/dsinx*dsinx/dx=5sin ⁴xcosxy=cos(4x+3)dy/dx=dcos(4x+3)/d(4x+3)*d(4x+3)/dx=-sin(4x+3)*4=-4sin(4x+3)...