\(\text{Thực hiện phép tính:}\)
\(\text{a) }\)\(\sqrt{75}+\sqrt{48}-\sqrt{300}\)
\(\text{b) }\)\(\sqrt{166}+2\sqrt{40b}-3\sqrt{90b}\left(b\ge0\right)\)
\(\text{c) }\)\(\left(\sqrt{28}-\sqrt{12}-\sqrt{7}\right)\sqrt{7}+2\sqrt{21}\)
\(\text{d) }\)\(2\sqrt{40\sqrt{12}}-2\sqrt{\sqrt{75}}-3\sqrt{5\sqrt{48}}\)
a: \(=5\sqrt{3}+4\sqrt{3}-10\sqrt{3}=-\sqrt{3}\)
b:Sửa đề: \(\sqrt{10b}+2\sqrt{40b}-3\sqrt{90b}\)
\(=\sqrt{10b}+4\sqrt{10b}-9\sqrt{10b}\)
\(=-4\sqrt{10b}\)
c: \(=\left(2\sqrt{7}-2\sqrt{3}-\sqrt{7}\right)\cdot\sqrt{7}+2\sqrt{21}\)
\(=7-2\sqrt{21}+2\sqrt{21}\)
=7
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