Answer
$\dfrac{2}{p+\sqrt{p(p-2)}}
$
Work Step by Step
Rationalize the numerator by multiplying $\sqrt{p}+\sqrt{p-2}$ to both the numerator and the denominator to have:
$=\dfrac{\sqrt{p}-\sqrt{p-2}}{\sqrt{p}} \cdot \dfrac{\sqrt{p}+\sqrt{p-2}}{\sqrt{p}+\sqrt{p-2}}
\\=\dfrac{p-(p-2)}{p+\sqrt{p(p-2)}}
\\=\dfrac{p-p-(-2)}{p+\sqrt{p(p-2)}}
\\=\dfrac{0+2}{p+\sqrt{p(p-2)}}
\\=\dfrac{2}{p+\sqrt{p(p-2)}}
$
