By using horizontal method,

We have;

= (x³ – 5x² + 3x + 1) × (x² – 3)

= x²(x³ – 5x² + 3x + 1) – 3(x³ – 5x² + 3x +1)

= x⁵ – 5x⁴ + 3x³ + x² – 3x³ + 15x² – 9x – 3

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

We get;

= x⁵ – 5x⁴ + 3x³ – 3x³ + x² + 15x² – 9x – 3

= x⁵ – 5x⁴ +16x² – 9x – 3