Question 45: Collapse the expression \(B=x \cdot\left(3 x^{2}-x+5\right)-\left(2 x^{3}+3 x-16\right)-x \cdot\left(x^{2}-x+2\right)\) we get

\(\begin{aligned} &B=x \cdot\left(3 x^{2}-x+5\right)-\left(2 x^{3}+3 x-16\right)-x \cdot \left(x^{2}-x+2\right) \\ &B=3 x^{3}-x^{2}+5 x-2 x^{3}-3 x+16-x^{ 3}+x^{2}-2 x \\ &B=3 x^{3}-3 x^{3}+x^{2}-x^{2}+5 x-5 x+16 \\ &B=16 . \end{aligned}\)