I assume you mean divide using the conjugate to rationalize the denominator and express the result in standard rectangular form.
[tex]\dfrac{2+i}{1+i} = \dfrac{2+i}{1+i} \cdot \dfrac{1-i}{1-i} = \dfrac{2(1)-i^2-2i+i}{1^2+1^2} = \frac 3 2 - \frac 1 2 i[/tex]
