y'等于e^x^2加x.2x.e^x^2等于(2x^2加1)e^x^2,y''等于4x.e^x^2加(2x^2加1).2x.e^x^2
y'=[xe^(x²)]'=e^(x²) +xe^(x²)(x²)'=e^(x²)+2x²e^(x²)y''=e^(x²)(x²)'+4xe^(x²)+2x²e^(x²)(x²)'=2xe^(x²)+4xe^(x²)+4x³e^(x²)=6xe^(x²)+4x³e^(x²)
