Suppose f(x)f(x)f(x) is a differentiable function such that f(x)f′(x)=xf(x)f'(x) = xf(x)f′(x)=x. If f(0)=2f(0) = 2f(0)=2, what is f(x)f(x)f(x)?
f(x)=x2+4f(x) = \sqrt{x^2+4}f(x)=x2+4
f(x)=x2+2f(x) = x^2+2f(x)=x2+2
f(x)=ex+1f(x) = e^x + 1f(x)=ex+1
f(x)=x+4f(x) = \sqrt{x+4}f(x)=x+4