Ta có :
\(a-b=12\)
\(\Rightarrow\left(a-b\right)^2=12^2\)
\(\Rightarrow a^2-2ab+b^2=144\)
\(\Rightarrow\left(a^2+b^2\right)-2ab=144\)
\(\Rightarrow154-2ab=144\) (vì \(a^2+b^2=154\))
\(\Rightarrow2ab=10\)
\(\Rightarrow ab=5\)
Do đó \(a^3-b^3=\left(a-b\right)\left(a^2+ab+b^2\right)=\left(a-b\right)\left[\left(a^2+b^2\right)+ab\right]=12\left(154+5\right)=12.159=1908\)
Vậy \(a^3-b^3=1908\)
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