Evaluate ∫1z2+4z+8dz\int \frac{1}{z^2 + 4z + 8} dz∫z2+4z+81dz.
12arctan(z+22)+C\frac{1}{2}\arctan(\frac{z+2}{2}) + C21arctan(2z+2)+C
arctan(z+2)+C\arctan(z+2) + Carctan(z+2)+C
14arctan(z2)+C\frac{1}{4}\arctan(\frac{z}{2}) + C41arctan(2z)+C
12ln(z2+4z+8)+C\frac{1}{2}\ln(z^2+4z+8) + C21ln(z2+4z+8)+C