a: \(=\dfrac{5}{9}\cdot\dfrac{4}{7}\cdot\dfrac{14}{3}=\dfrac{40}{27}\)
b: \(=\sqrt{\dfrac{49}{16}\cdot\dfrac{64}{25}\cdot\dfrac{196}{81}}=\dfrac{7}{4}\cdot\dfrac{8}{5}\cdot\dfrac{14}{9}=\dfrac{196}{45}\)
c: \(=\sqrt{\dfrac{64\cdot343}{567}}=\dfrac{56}{9}\)
\(\sqrt{\dfrac{25}{81}.\dfrac{16}{49}.\dfrac{196}{9}}\)
\(=\dfrac{5}{9}.\dfrac{4}{7}.\dfrac{14}{3}\)
\(=\dfrac{5.4.14}{9.7.3}\)
`=40/27`
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\(\sqrt{3\dfrac{1}{16}.2\dfrac{14}{25}.2\dfrac{34}{81}}\)
\(=\sqrt{\dfrac{49}{16}.\dfrac{64}{25}.\dfrac{196}{81}}\)
`=7/4 . 8/5 . 14/9`
\(=\dfrac{7.8.14}{4.5.9}\)
`=196/45`
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\(\dfrac{\sqrt{640}.\sqrt{34,3}}{\sqrt{567}}\)
\(=\dfrac{\sqrt{640:10}.\sqrt{34,3.10}}{\sqrt{567}}\)
\(=\dfrac{\sqrt{64}.\sqrt{343}}{\sqrt{567}}\)
\(=\dfrac{\sqrt{64.343}}{\sqrt{567}}\)
\(=\sqrt{\dfrac{64.343}{567}}\)
`=56/9`
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\(\sqrt{21,6}.\sqrt{810}.\sqrt{11^2-5^2}\)
\(=\sqrt{21,6.810}.\sqrt{121-25}\)
\(=\sqrt{216.81}.\sqrt{96}\)
\(=\sqrt{216.81.96}\)
`=`\(1296\)
