Question

What is the product of (3a 2)(4a2 – 2a 9)?
a. 12a3 − 2a 18
b. 12a3 6a 9
c.12a3 − 6a2 23a 18
d. 12a3 2a2 23a 18?

Answer 1

The answer is 12a^3 + 2a^2 + 23a + 18 

Or in other words, the answer is D 

Answer 2

The correct answer is: Option (d) $12a^3 +2a^2 + 23a + 18$

Explanation:

Given expression:

$(3a+2)(4a^2-2a+9) \\ Simplify: \\ 3a(4a^2-2a+9) + 2(4a^2-2a+9) \\ 12a^3 - 6a^2 + 27a + 8a^2 - 4a +18 \\ 12a^3 +2a^2 + 23a + 18$

Hence the correct answer is: Option (d) $12a^3 +2a^2 + 23a + 18$