6.10. Represent the following numbers in the form $\sqrt{a} \pm \sqrt{b}$, where $a$ and $b$ are natural numbers:
a) $\sqrt{3+2 \sqrt{2}}$
b) $\sqrt{9+4 \sqrt{5}}$
c) $\sqrt{7-2 \sqrt{10}}$.
6.10. Using the formula from problem 6.9, we get the following answers: a) $1+\sqrt{2} ;$ b) $2+\sqrt{5}$; c) $\sqrt{5}-\sqrt{2}$.