Đáp án:
$\begin{array}{l}
c){72^2} - 56.72 + {28^2}\\
= {72^2} - 2.28.72 + {28^2}\\
= {\left( {72 - 28} \right)^2}\\
= {44^2}\\
= 484\\
d)8{x^3}.6 + 60{x^2} - 150{x^2} + 60x - 8\\
= 8.{\left( { - \dfrac{1}{2}} \right)^3}.6 + 60.{\left( { - \dfrac{1}{2}} \right)^2} - 150.{\left( { - \dfrac{1}{2}} \right)^2} + 60.\left( { - \dfrac{1}{2}} \right) - 8\\
= 8.\dfrac{{ - 1}}{8}.6 + 60.\dfrac{1}{4} - 150.\dfrac{1}{4} - 60.\dfrac{1}{2} - 8\\
= - 6 + 15 - 35 - 30 - 8\\
= - 64\\
e)125{x^3} + 150{x^2} + 60x - 8\\
= {\left( {5x} \right)^3} + 3.25{x^2}.2 + 3.5x.4 - {2^3}\\
= {\left( {5x - 2} \right)^3}\\
= {\left( {5.\dfrac{{ - 1}}{5} - 2} \right)^3}\\
= {\left( { - 3} \right)^3}\\
= - 27\\
f)27{x^3} - 27{x^2} + 9x - 1\\
= {\left( {3x} \right)^3} - 3.9{x^2}.1 + 3.3x.1 - 1\\
= {\left( {3x - 1} \right)^3}\\
= {\left( {3.\dfrac{{ - 2}}{3} - 1} \right)^3}\\
= {\left( { - 3} \right)^3}\\
= - 27
\end{array}$
