Find each of the following products:
(9x2 – x + 15) × (x2 – 3)
By using horizontal method,
We have;
= (9x2 – x + 15) × (x2 – 3)
= x2(9x2 – x +15) – 3(9x2 – x + 15)
= 9x4 – x3 + 15x2 – 27x2 + 3x – 45
= 9x4 - x3 – 12x2 + 3x – 45