### Home > A2C > Chapter 13 > Lesson 13.2.3 > Problem 13-132

13-132.

Consider the function

. Homework Help ✎ Make a complete graph of

*f*(*x*).Write a simpler trig function that is represented by the same graph.

Now use the angle sum identity to expand and simplify

. Does your work in part (c) agree with your graphical results from parts (a) and (b)? Explain.

*f*(*x*) = −sin(*x*)

Yes, they do agree.