Question

Evaluate the function f(x) = x² +7x+3 at the given values of the independent variable and simplify.a. f(3) b. f(x+7) c. f(-x)a. f(3) = (Simplify your answer.)b. f(x+7)=(Simplify your answer.)c. f(-x)=(Simplify your answer.)

Answer 1

The given function is

`f(x)=x^2+7x+3`

a. f(3)

To get f(3) substitute x = 3 into f(x)

`\begin{gathered} f(3)=3^2+7(3)+3 \\ f(3)=9+21+3_{} \\ f(3)=33 \end{gathered}`

b. f(x+7)

Using the same procedure it follows:

`f(x+7)=(x+7)^2+7(x+7)+3`

Simplify the expression

`\begin{gathered} f(x+7)=x^2+14x+49+7x+49+3 \\ f(x+7)=x^2+21x+101 \end{gathered}`

c. f(-x)

This gives

`\begin{gathered} f(-x)=(-x)^2+7(-x)+3 \\ f(-x)=x-7x+3 \end{gathered}`