A function fff is defined as f(x)=∫0xe−t2dtf(x) = \int_0^x e^{-t^2} dtf(x)=∫0xe−t2dt. Which of the following is the derivative of g(x)=f(x2)g(x) = f(x^2)g(x)=f(x2)?
e−x2e^{-x^2}e−x2
2xe−x42x e^{-x^4}2xe−x4
x2e−x2x^2 e^{-x^2}x2e−x2
e−x4e^{-x^4}e−x4