Đáp án:
$\begin{array}{l}
a){85^2} - {15^2} = \left( {85 + 15} \right)\left( {85 - 15} \right)\\
= 100.70\\
= 7000\\
b){73^2} - {13^2} - {10^2} + 20.13\\
= {73^2} - {13^2} + 20.13 - {10^2}\\
= {73^2} - {\left( {13 - 10} \right)^2}\\
= {73^2} - {3^3}\\
= \left( {73 + 3} \right)\left( {73 - 3} \right)\\
= 76.70\\
= 6320\\
c){96^3} + {12.96^2} + 3.96.16 + 64\\
= {96^3} + {3.96^2}.4 + {3.96.4^2} + {4^3}\\
= {\left( {96 + 4} \right)^3}\\
= {100^3}\\
= 1000000\\
d)\dfrac{{{{96}^3} + {{86}^3}}}{{182}} - 96.86\\
= \dfrac{{\left( {96 + 86} \right)\left( {{{96}^2} - 96.86 + {{86}^2}} \right)}}{{182}} - 96.86\\
= {96^2} - 96.86 + {86^2} - 96.86\\
= {96^2} - 2.96.86 + {86^2}\\
= {\left( {96 - 86} \right)^2}\\
= {10^2}\\
= 100
\end{array}$
