Question

Find for the following functions. f(x) = 9x2 – 2x – 9 g(x) = 11x – 9
A) 99x3 – 103x2 + 18x – 180
B)99x3 – 103x2 – 81x + 81
C)99x3 – 103x2 – 81x – 81
D)99x3 + 81x2 – 103x + 81

Answer 1

For this case we have the following functions:

$f (x) = 9x ^ 2-2x-9\\g (x) = 11x-9$

We must find the product of both functions:

$f (x) * g (x) = (9x ^ 2-2x-9) * (11x-9)$

We apply distributive property term to term:

$f (x) * g (x) = 99x ^ 3-81x ^ 2-22x ^ 2 + 18x-99x + 81$

We add similar terms:

$f (x) * g (x) = 99x ^ 3-103x ^ 2-81x + 81$

Answer:

Option B