Answer
$F(x)=4x-3\arctan x + \frac{3\pi}{4} -4$
Work Step by Step
Note that the antiderivative of a constant is that constant multiplied by the variable. Note that $\frac{d}{dx} \arctan x=\frac{1}{1+x^2}$. Thus
$$F(x)=4x-3\arctan x +C$$
Then use the given initial condition to solve for $C.$
$$0=4(1)-3\arctan 1 + C$$
$$0=4-\frac{3\pi}{4} +C$$
$$C=\frac{3\pi}{4}-4$$.