The given problem asks to evaluate the function $(f + g)(-6)$ where the functions are:

$f(x) = x + 3 \quad \text{and} \quad g(x) = x^2 - 2.$

To find $(f + g)(-6)$, we first need to add the two functions $f(x)$ and $g(x)$, then substitute $x = -6$ into the resulting function.

Step 1: Adding $f(x)$ and $g(x)$

$(f + g)(x) = f(x) + g(x) = (x + 3) + (x^2 - 2) = x^2 + x + 1.$

Step 2: Substituting $x = -6$ into $f + g$

$(f + g)(-6) = (-6)^2 + (-6) + 1 = 36 - 6 + 1 = 31.$

Thus, $(f + g)(-6) = 31$.

Would you like further clarification or more details? Here are five related questions you might find interesting:

1. How do you find the value of $f(-6)$ and $g(-6)$ separately?
2. Can you evaluate $(f \cdot g)(-6)$?
3. How would you graph $f(x)$ and $g(x)$ on the same plane?
4. How does adding functions differ from composing functions $(f \circ g)(x)$?
5. What happens if you subtract the functions $f(x) - g(x)$ and evaluate at $x = -6$?

Tip: Always simplify functions first before substituting values to avoid calculation errors.