### Home > INT3 > Chapter Ch12 > Lesson 12.2.3 > Problem 12-111

12-111.

Consider the function

Make a complete graph of the function.

Write a simpler trigonometric function that is represented by the same graph.

Which trig function passes through the origin?

Now use the angle sum identity to expand and simplify

. Review the Math Notes box in this lesson and problem 12-108 for the Angle Sum Identities.

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

Your answers should agree.