Question

What is the range of this?

Answer 1

You have the correct answer. The answer is choice D) Set of real numbers less than -1. Nice job. 

As x approaches negative infinity, then -3^x approaches 0 though never actually gets there. So overall, f(x) approaches -1 as x approaches negative infinity. Plugging in x = 0 leads to f(x) = -2 which supports choice D.