Question

Express your answer as a polynomial in standard form.f(x) = -3x + 1g(x) = 3x2 + 4x – 15Find: f(g(x))

Answer 1

SOLUTION

Step1; Write out the expression

$\begin{gathered} f(x)=-3x+1 \\ g(x)=3x^2+4x-15 \end{gathered}$

Step2: Substitute the expression of g(x) for x into the F(x), we have

$\begin{gathered} f(g(x))=-3(3x^2+4x-15)+1 \\ =-9x^2-12x+45+1 \\ \end{gathered}$

Then

$f(g(x))=-9x^2-12x+46$

Therefore, F(g(x))=-9x²-12x+46