Answer
See below.
Work Step by Step
In order to solve such a problem we need to multiply the numerator and denominator by the denominator's conjugate. E.g.:
$\frac{2+i}{1+i}=\frac{2+i}{1+i}=\frac{(2+i)(1-i)}{(1+i)(1-i)}=\frac{2-2i+i+1}{1-i+i+1}=\frac{3-i}{2}$