ANSWER
-2 shift the graph of the basic function down by 2 units.
EXPLANATION
The given cosine function is:
[tex]y = - 2 - 3 \cos(x + \pi) [/tex]
This equation can be rewritten as:
[tex]y = - 3 \cos(x + \pi) + - 2[/tex]
We compare this to
[tex]y = a \cos(bx + c) + d[/tex]
The effect d has on the graph is that, it shifts the graph up by d units.
If d is negative the graph shifts down by d units.
Since d=-2, the graph will shift down by 2 units.
