Question 2: Reducing the expression \(\frac{1}{2} x^{3} \cdot(4-x)(x+1) \) we get
\(\frac{1}{2} x^{3} \cdot(4-x)(x+1) =\left(2 x^{3}-\frac{1}{2} x^{4 }\right)(x+1)=2 x^{4}+2 x^{3}-\frac{1}{2} x^{5}-\frac{1}{2} x^{4 }=-\frac{1}{2} x^{5}+\frac{3}{2} x^{4}+2 x^{3}\)
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