Find each of the following products:(x3 – 2x2 + 5) × (4x - 1)

1.	Find each of the following products:(x3 – 2x2 + 5) × (4x - 1)
Answer» By using horizontal method, We have; = (x³ – 2x² + 5) × (4x – 1) = 4x(x³ – 2x² + 5) – 1(x³ – 2x² + 5) = 4x⁴ – 8x³ + 20x – 1x³ + 2x² – 5 By arranging the expression in the form of descending powers of x, We get; = 4x⁴ – 8x³ – x³ + 2x² + 20x – 5 = 4x⁴ – 9x³ + 2x² + 20x – 5

Answer»

By using horizontal method,

We have;

= (x³ – 2x² + 5) × (4x – 1)

= 4x(x³ – 2x² + 5) – 1(x³ – 2x² + 5)

= 4x⁴ – 8x³ + 20x – 1x³ + 2x² – 5

By arranging the expression in the form of descending powers of x,

We get;

= 4x⁴ – 8x³ – x³ + 2x² + 20x – 5

= 4x⁴ – 9x³ + 2x² + 20x – 5

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