\[\boxed{\text{929.}\text{\ }еуроки - ответы\ на\ пятёрку}\]
\[\textbf{а)}\ 327³ + 173³ = (327 + 173)\]
\[\left( 327^{2} - 327 \cdot 173 + 173^{2} \right) =\]
\[= 500 \cdot\]
\[\cdot \left( 327^{2} - 327 \cdot 173 + 173^{2} \right) -\]
\[делится\ на\ 500.\]
\[\textbf{б)}\ 731³ - 631^{3} =\]
\[= (731 - 631)\]
\[\left( 731^{2} + 731 \cdot 631 + 631^{2} \right) =\]
\[= 100 \cdot\]
\[\cdot \left( 731^{2} + 731 \cdot 631 + 631^{2} \right) -\]
\[делится\ на\ 100.\]
\[\textbf{в)}\ 211³ + 129³ =\]
\[= (211 + 129)\]
\[\left( 211^{2} + 211 \cdot 129 + 129^{2} \right) =\]
\[= 340 \cdot\]
\[\cdot (\left( 211^{2} + 211 \cdot 129 + 129^{2} \right) =\]
\[= 20 \cdot 17 \cdot\]
\[\cdot \left( 211^{2} + 211 \cdot 129 + 129^{2} \right) -\]
\[делится\ на\ 17.\]
\[\textbf{г)}\ 356³ - 245^{3} = (356 - 245)\]
\[\left( 356^{2} + 356 \cdot 245 + 245^{2} \right) =\]
\[= 111 \cdot\]
\[\cdot \left( 356^{2} + 356 \cdot 245 + 245^{2} \right) =\]
\[= 3 \cdot 37 \cdot\]
\[\cdot \left( 356^{2} + 356 \cdot 245 + 245^{2} \right) -\]
\[делится\ на\ 3.\]