Question

Tính hợp lí nếu có thể:

a,\(\left(1,2-\sqrt{\dfrac{1}{4}}\right)\) : \(1\dfrac{1}{20}\) + \(\left|\dfrac{3}{4}-1,25\right|\) - \(\left(-\dfrac{3}{2}\right)^2\)

Giúp mk vs mk cần gấp lắm

Answer 1

Tính hợp lí nếu có thể:

a,\(\left(1,2-\sqrt{\dfrac{1}{4}}\right):1\dfrac{1}{20}+\left|\dfrac{3}{4}-1,25\right|-\left(-\dfrac{3}{2}\right)^2\)

\(=\left(\dfrac{12}{10}-\dfrac{1}{2}\right):\dfrac{21}{20}+\left|\dfrac{3}{4}-\dfrac{5}{4}\right|-\dfrac{9}{4}\)

\(=\dfrac{7}{10}\cdot\dfrac{20}{21}+\left|-\dfrac{1}{2}\right|-\dfrac{9}{4}\)

\(=\dfrac{2}{3}+\dfrac{1}{2}-\dfrac{9}{4}=\dfrac{8+6-27}{12}=-\dfrac{13}{12}\)

Answer 2

\(\left(1,2-\sqrt{\dfrac{1}{4}}\right):1\dfrac{1}{20}+\left|\dfrac{3}{4}-1,25\right|-\left(-\dfrac{3}{2}\right)^2\\ =\left(1,2-\dfrac{1}{2}\right):\dfrac{21}{20}+\left|\dfrac{3}{4}-\dfrac{5}{4}\right|-\dfrac{9}{4}\\ =\dfrac{7}{10}.\dfrac{20}{21}+\dfrac{1}{2}-\dfrac{9}{4}\\ =\dfrac{1}{3}+\dfrac{1}{2}-\dfrac{9}{4}=\dfrac{5}{6}-\dfrac{9}{4}\\ =-\dfrac{17}{12}\)