Question

F(x) = (x + 3)²; find f(a)

Answer 1

Answer:
`(a + 3)^2` or (
`a^2 + 6a + 9`) (Depending out what form they want the answer)

Explanation:

When plugging in values to f(x), we are replacing the value of x in the function. In this case, we are replacing the x in (x + 3
`)^2` with an a. This will give you
`(a + 3)^2`.

If you wanted to expand this, you just need to multiply the parenthesis (note, this can also be done before plugging in the value, and plugging in after you have expanded the parenthesis)

You would get:
`(a + 3)(a + 3) = a^2 + 6a + 9`

I hope this helps, if they didn't explicitly say to expand the parenthesis, then I'm sure my first answer would work fine for you. If you need anything explained let me know.