Ques 13 could you please help?

enter image source here

1 Answer
Dec 8, 2017

The answer is D.

Explanation:

A. Incorrect. The "image set" refers to the entire domain of #f(x)#. Option A describes the range.

B. Incorrect. This wrongly uses interval notation do describe the domain by including 4 in the interval. The domain of #f(x)# is #[1,4)#, not #[1,4]#.

C. Incorrect. As #f# increases, then decreases within the interval from #(1,3).

D. Correct. We can see from the graph that #f# is decreasing from 2 to 3.

E. Incorrect. If we graph the inverse of #f(x)# by reflecting #f(x)# over #y=x# (or imagining the graph), #f^-1(x)# does not pass the vertical line test.