# How do you evaluate the function f (x) = 3x^2 + 3x -2 for f (a) + f (2)?

Nov 27, 2015

$f \left(a\right) + f \left(2\right) = 3 {a}^{2} + 3 a + 14$

#### Explanation:

When evaluating a function $f \left(x\right)$ at some specific value, you simply replace $x$ with that value wherever $x$ appears in the function.
So

$f \left(a\right) = 3 {a}^{2} + 3 a - 2$

and

$f \left(2\right) = 3 {\left(2\right)}^{2} + 3 \left(2\right) - 2 = 12 + 6 - 2 = 16$

Thus

$f \left(a\right) + f \left(2\right) = \left(3 {a}^{2} + 3 a - 2\right) + 16 = 3 {a}^{2} + 3 a + 14$