Tham khảo: https://hoc24.vn/cau-hoi/.1666434944019
\(a,-4\sqrt{\dfrac{4}{25}}+7\sqrt{0,16}+6\sqrt{0,04}-0\sqrt{2003}\\ =-4\cdot0,4+7\cdot0,4+6\cdot0,2\\ =2,4\)
\(b,\dfrac{\sqrt{36}}{\sqrt{25}}\cdot\dfrac{1}{4}-\dfrac{\sqrt{49}}{\sqrt{64}}\cdot\dfrac{\sqrt{36}}{\sqrt{25}}\\ =\dfrac{6}{5}\cdot\dfrac{1}{4}-\dfrac{7}{8}\cdot\dfrac{6}{5}=\dfrac{3}{10}-\dfrac{21}{20}=-\dfrac{3}{4}\)
\(c,\sqrt{12100}=\sqrt{12}\cdot\sqrt{100}=2\sqrt{3}\cdot10=20\sqrt{3}\)
\(d,\sqrt{\dfrac{49}{100}}=\dfrac{7}{10}\)
\(e,4\sqrt{5}+3\sqrt{20}-2\sqrt{80}=4\sqrt{5}+6\sqrt{5}-8\sqrt{5}=2\sqrt{5}\)
\(f,12\sqrt{3}-5\sqrt{27}-7\sqrt{12}=12\sqrt{3}-15\sqrt{3}-14\sqrt{3}=-17\sqrt{3}\)
a: Ta có: \(-4\sqrt{\dfrac{4}{25}}+7\cdot\sqrt{0.16}+6\cdot\sqrt{0.04}-0\sqrt{2003}\)
\(=-4\cdot\dfrac{2}{5}+7\cdot\dfrac{2}{5}+6\cdot\dfrac{1}{5}\)
\(=\dfrac{6}{5}+\dfrac{6}{5}=\dfrac{12}{5}\)
b: Ta có: \(\dfrac{\sqrt{36}}{\sqrt{25}}\cdot\dfrac{1}{4}-\dfrac{\sqrt{49}}{\sqrt{64}}\cdot\dfrac{\sqrt{36}}{\sqrt{25}}\)
\(=\dfrac{6}{5}\cdot\dfrac{1}{4}-\dfrac{7}{8}\cdot\dfrac{6}{5}\)
\(=\dfrac{3}{10}-\dfrac{21}{20}\)
\(=\dfrac{-15}{20}=-\dfrac{3}{4}\)
c: \(\sqrt{12100}=110\)
d: \(\sqrt{\dfrac{49}{400}}=\dfrac{7}{20}\)
e: Ta có: \(4\sqrt{5}+3\sqrt{20}-2\sqrt{80}\)
\(=4\sqrt{5}+6\sqrt{5}-8\sqrt{5}\)
\(=2\sqrt{5}\)
f: Ta có: \(12\sqrt{3}-5\sqrt{27}-7\sqrt{12}\)
\(=12\sqrt{3}-15\sqrt{3}-14\sqrt{3}\)
\(=-17\sqrt{3}\)
