Question

What is the product of (3a + 2)(4a^2 – 2a + 9)

Answer 1

`\large\boxed{(3a+2)(4a^2-2a+9)=12a^3+2a^2+23a+18}`

Explanation:

`(3a+2)(4a^2-2a+9)\qquad\text{use FOIL:}\ (a+b)(c+d)=ac+ad+bc+bd\\\\=(3a)(4a^2)+(3a)(-2a)+(3a)(9)+(2)(4a^2)+(2)(-2a)+(2)(9)\\\\=12a^3-6a^2+27a+8a^2-4a+18\qquad\text{combine like terms}\\\\=12a^3+(-6a^2+8a^2)+(27a-4a)+18\\\\=12a^3+2a^2+23a+18`