Explanation:
I take it this is meant to be a multiplication, right ?
not a "function of function", which would be symbolized by a little empty circle.
to multiply 2 function means basically the same as to add, subtract or divide 2 functions : to apply the arithmetic operation in both expressions.
(f×g)(x) = (-2x² + 4x)(x² + 18x + 77) =
= -2x⁴ - 36x³ - 154x² + 4x³ + 72x² + 308x =
= -2x⁴ - 32x³ - 82x² + 308x