Hey Colin,

For those questions you will need to use the graphs of the functions to find the values that you need. You just need to be careful with the order in which you plug in the numbers in the functions. For example, if the question was $\left(f\circ g\right)\left(2\right)$ you would need to find first $g(2)$ and use that to plug into $f$:

$\left(f \circ g \right) \left( 2 \right) = f \left( g \left(  2 \right) \right) = f \left( -2 \right) = -4$

Something similar happens when you add or subtract functions, in that case you just need to plug in the value into each function and then add or subtract accordingly. For example, if we wanted $\left( g-f\right) \left(2\right)$, we would need to first find $g\left( 2\right)$ and $f\left(2\right)$, and then subtract:

$\left( g-f\right) \left(2\right) = g\left( 2 \right) - f \left( 2 \right) = -1 - 2 = -3$

Cheers,

David