Answer:
(a) -3
Explanation:
The value of f(x) approaches 3cos(π) = -3 as x approaches π from either direction. The limit is -3.
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Additional comment
The fact that the function is defined to have a different value at x=π simply means there is a jump discontinuity there. The function is not continuous, because the limit and the function value differ. That doesn't detract from the fact that there is a limit, and it is -3.