Let f (x) = x2 + 3x - 4 and g (x) = x + 5. Find f (x) • g (x).

f (x) • g (x)

SImply multiply the functions,

(x2 + 3x-4) (x+5)

Distribute then simplify.

x (x2 + 3x-4) + 5 (x2 + 3x-4)

Further distribute x and 5, respectively, to terms inside parentheses, and combine like terms.

x3 + 3x2 - 4 + 5x2 + 15x - 20

Simplify for the last time.

The final and simplified expression or answer is: x3 + 8x2 + 11x - 20

f (x) • g (x) = x3 + 8x2 + 11x - 20