Answer: (c * d)(x) = 4x^3 + 18x^2 - 10x
Work Shown:
I'm assuming the dot means multiplication. If so, then,
(c * d)(x) = c(x)*d(x)
(c * d)(x) = [ c(x) ] * [ d(x) ]
(c * d)(x) = (4x-2)(x^2+5x) .... substitution
(c * d)(x) = 4x(x^2+5x) - 2(x^2+5x) ... distribute
(c * d)(x) = 4x(x^2)+4x(5x) - 2(x^2)-2(5x) ... distribute again
(c * d)(x) = 4x^3 + 20x^2 - 2x^2 - 10x
(c * d)(x) = 4x^3 + 18x^2 - 10x
