Converting to a partial fraction. I'm trying to do an inverse Laplace operation on $I(s)$ shown below but I'm struggling on finding what $A$ & $C$ are on the partial fraction and how to do it. I calculated what $B$ equals by making $s=0$.
$$I(s)=\frac{1}{s^2(R+L)}=\frac{A}{s}+\frac{B}{s^2}+\frac{C}{R+Ls} \\
1=As(R+Ls)+B(R+Ls)+Cs^2 \\
B=\frac{1}{R}$$

Compute the derivative of both sides at $s = 0$; we have
$$0 = AR + 2 AL s + BL + 2 C s$$
Evaluating at $s = 0$ gives
$$AR + BL = 0 \implies A = -\frac{BL}{R} = -\frac{L}{R^2}$$
To find $C$, perhaps evaluate at $s = 1$ with the previously found values for $A$ and $B$.
