Решите №169(2,6,9).№167(1,2).

Решите задачу:

$(1- \sqrt{x} )(1+ \sqrt{x} +x)=1-x \sqrt{x} \\\ ( \sqrt{m} - \sqrt{n} )(m+n+ \sqrt{mn} )=m\sqrt{m} -n \sqrt{n}$

$\frac{ \sqrt{a}+ \sqrt{b} }{a \sqrt{a}+b \sqrt{b} } = \frac{ \sqrt{a}+ \sqrt{b} }{(\sqrt{a}+ \sqrt{b} )(a+b- \sqrt{ab}) } =\frac{ 1 }{a+b- \sqrt{ab} }$

$\frac{9-2 \sqrt{3} }{3 \sqrt{6}-2 \sqrt{2} } = \frac{ \sqrt{3}(3 \sqrt{3}-2) }{\sqrt{2} (3 \sqrt{3}-2 ) } = \frac{ \sqrt{3} }{\sqrt{2} } = \sqrt{1.5}$

$\frac{( { \sqrt{10}-1)^2-3} }{ \sqrt{10}+ \sqrt{3}-1 } = \frac{ { (\sqrt{10}-1- \sqrt{3})(\sqrt{10}-1+ \sqrt{3}) } }{ \sqrt{10}+ \sqrt{3}-1 } =\sqrt{10}-1- \sqrt{3}$