Question

Find each of the following products:
(i) (4a + 5b) × (5a − 6b)
(ii) (6x² − x + 8) × (x² − 3)

Answer 1

$$\begin{gathered} \left(i\right) \\ \left(4a+5b\right)\times \left(5a-6b\right) \\ =20a^2-24ab+25ab-30b^2 \\ =20a^2+ab-30b^2 \\ \left(ii\right) \\ \left(6x^2-x+8\right)\times \left(x^2-3\right) \\ =6x^4-18x^2-x^3+3x+8x^2-24 \\ =6x^4-x^3-18x^2+8x^2+3x-24 \\ =6x^4-x^3-10x^2+3x-24 \end{gathered}$$