\(P=\frac{\left(35-13\right)\left(35^2+35.13+13^2\right)}{48}-35.13\)
\(=\frac{11\left(35^2+13^2+35.13\right)}{24}-\frac{24.35.13}{24}\)
\(=\frac{11.35^2+11.13^2+11.35.13-24.35.13}{24}\)
\(=\frac{11.35^2+11.13^2-13^2.24}{24}=\frac{11.35^2-13^3}{24}\)
Đến đay tính là ra