Question: Find the product:
(x3 − 2x2 + 5) × (4x − 1)
Solution:
By horizontal method:
$\left(x^{3}-2 x^{2}+5\right) \times(4 x-1)$
$=4 x\left(x^{3}-2 x^{2}+5\right)-1\left(x^{3}-2 x^{2}+5\right)$
$=4 x^{4}-8 x^{3}+20 x-x^{3}+2 x^{2}-5$
$=4 x^{4}-9 x^{3}+2 x^{2}+20 x-5$
