1, (√18 + √32 - √50). √2 2,(15√50 + 5√200 - 3√450): √10

$\textit{Đáp án + Giải thích các bước giải:}$

$1,(\sqrt{18}+\sqrt{32}-\sqrt{50}).\sqrt{2}$

$=\sqrt{18}.\sqrt{2}+\sqrt{32}.\sqrt{2}-\sqrt{50}.\sqrt{2}$

$=\sqrt{36}+\sqrt{64}+\sqrt{100}$

$=6+8-10$

$=4$

$2,(15\sqrt{50}+5\sqrt{200}-3\sqrt{450}):\sqrt{10}$

$=15\sqrt{50}:\sqrt{10}+5\sqrt{200}:\sqrt{10}-3\sqrt{450}:\sqrt{10}$

$=15\sqrt{5}+5\sqrt{20}-3\sqrt{45}$

$=15\sqrt{5}+5\sqrt{5}.\sqrt{4}-3\sqrt{5}.\sqrt{9}$

$=15\sqrt{5}+5.2\sqrt{5}-3.3\sqrt{5}$

$=15\sqrt{5}+10\sqrt{5}-9\sqrt{5}$

$=\sqrt{5}(15+10-9)$

$=16\sqrt{5}$