1)
\(\sqrt{0,36}.\sqrt{\dfrac{25}{16}}+\left(-\dfrac{1}{2}\right)^2\)
\(=\dfrac{3}{5}.\dfrac{5}{4}+\dfrac{1}{4}\)
\(=\dfrac{3}{4}+\dfrac{1}{4}\)
\(=1\)
2)
\(\left(\dfrac{1}{4}-\dfrac{1}{\sqrt{64}}\right):\left(\dfrac{3}{2}\right)^2\)
\(=\left(\dfrac{1}{4}-\dfrac{1}{8}\right):\dfrac{9}{4}\)
\(=\left(\dfrac{2}{8}-\dfrac{1}{8}\right):\dfrac{9}{4}\)
\(=\dfrac{1}{8}:\dfrac{9}{4}\)
\(=\dfrac{1}{8}.\dfrac{4}{9}\)
\(=\dfrac{1}{18}\)
3)
\(\sqrt{\dfrac{4}{81}}.\dfrac{27}{8}-\sqrt{0,49}.\dfrac{1}{7}\)
\(=\dfrac{2}{9}.\dfrac{27}{8}-\dfrac{7}{10}.\dfrac{1}{7}\)
\(=\dfrac{3}{4}-\dfrac{7}{10}.\dfrac{1}{7}\)
\(=\dfrac{3}{4}-\dfrac{1}{10}\)
\(=\dfrac{30}{40}-\dfrac{4}{40}\)
\(=\dfrac{13}{20}\)
d)
\(\sqrt{\dfrac{16}{81}}.\dfrac{27}{8}-\sqrt{0,25}.\left(-2\right)^2\)
\(=\dfrac{4}{9}.\dfrac{27}{8}-\dfrac{1}{2}.4\)
\(=\dfrac{3}{2}-\dfrac{1}{2}.4\)
\(=\dfrac{3}{2}-2\)
\(=-\dfrac{1}{2}\)
\(#NguyễnNgọcKhánhLinh-VietNam\)
