Question

bai 41:

a) \(\left(1+\dfrac{2}{3}-\dfrac{1}{4}\right).\left(\dfrac{4}{5}-\dfrac{3}{4}\right)^2\)

b) \(2:\left(\dfrac{1}{2}-\dfrac{2}{3}\right)^3\)

help me

Answer 1

a, \(\left(1+\dfrac{2}{3}-\dfrac{1}{4}\right).\left(\dfrac{4}{5}-\dfrac{3}{4}\right)^2=\left(\dfrac{5}{3}-\dfrac{1}{4}\right).\left(\dfrac{1}{20}\right)^2=\dfrac{17}{12}.\dfrac{1}{400}=\dfrac{17}{4800}\)

b, \(2:\left(\dfrac{1}{2}-\dfrac{2}{3}\right)^3=2:\left(-\dfrac{1}{2}\right)^3=2:-\dfrac{1}{8}=2.-8=-16\)

Answer 2

\(a.\left(1+\dfrac{2}{3}-\dfrac{1}{4}\right).\left(\dfrac{4}{5}-\dfrac{3}{4}\right)^2\)

\(=\left(\dfrac{5}{3}-\dfrac{1}{4}\right).\left(\dfrac{1}{20}\right)^2\)

\(=\left(\dfrac{17}{12}\right).\dfrac{1}{400}\)

\(=\dfrac{17}{4800}\)

\(b.2:\left(\dfrac{1}{2}-\dfrac{2}{3}\right)^3\)

\(=2:\left(-\dfrac{1}{6}\right)^3\)

\(=2:\left(-\dfrac{1}{216}\right)\)

\(=\left(-432\right)\)