a) \(\left(m-\dfrac{1}{4}\right)^3=\left(m^3-3m^2.\dfrac{1}{4}+3m\left(\dfrac{1}{4}\right)^2-\left(\dfrac{1}{4}\right)^3\right)\\ =\left(m^3-\dfrac{3}{4}m^2+\dfrac{3}{16}m-\dfrac{1}{64}\right)\)
b)\(\left(\dfrac{2}{3}-n\right)^3=\left(\dfrac{2}{3}\right)^3-3\left(\dfrac{2}{3}\right)^2n+3.\dfrac{2}{3}n^2-n^3\\ =\dfrac{8}{27}-\dfrac{4}{3}n+2n^2-n^3\)
c)\(m^3-125=m^3-5^3=\left(m-5\right)\left(m^2+5m+25\right)\)
d)\(m^3+\dfrac{1}{64}=m^3+\left(\dfrac{1}{4}\right)^3=\left(m+\dfrac{1}{4}\right)\left(m^2-\dfrac{1}{4}m+\dfrac{1}{16}\right)\)
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