设x^2=a则y=sin(a^2)∴dy/d(x^2)=dy/da=dsin(a^2)/da=cos(a^2)*da^2/da=2acos(a^2)，将a=x^2代入式中即可得dy/d(x^2)=2x^2cos(x^4).
dy/d(x^2)也就是对x^2求导数sin[(x^2)^2]所以2sin(x^2)*cos(x^2)
