Question

The graphs of two sine functions are shown below.

The function whose graph is B was obtained from the function whose graph is A by one of the following changes. That change was:

a phase shift

a period change

a change in amplitude

the addition of a negative constant

Answer 1

"a period change"

Explanation:

Simple ways of understanding transformations are:

Phase shift: 2 graphs would be shifted version of each other, all other things constant.

Period change: the 2 graphs would have different cycles, one would be compressed/stretched version of the other, all other things constant

Amplitude Change: The height/crest of the graphs would vary, that is the amplitude. All other things constant.

Addition of Negative constant: this would shift the 1 graph downwards with respect to the other graph, it is a vertical shift. All other things constant.

Now carefully looking at the 2 graphs given, we can see that the cycles are different. One is a more "relaxed", or "stretched" version of the other. This means, the period is changed.

2nd answer choice is right.