### Home > CALC > Chapter 6 > Lesson 6.3.4 > Problem 6-117

6-117.

**Multiple Choice:**Which of the following expressions is equal to? Homework Help ✎ I. 2 cos

*x*II. −2 cos

*x*sin*x*III. −sin 2

*x*I only

II only

III only

II and III

none

There may be more than one correct answer.