If f(x)=3x2f(x) = 3x^2f(x)=3x2, which of the following is NOT an antiderivative of f(x)f(x)f(x)?
x3+5x^3 + 5x3+5
3x33x^33x3
x3−100x^3 - 100x3−100
x3x^3x3