03 Take a Test fatima carrillo Mozilla Firefox httpswwwmathx

03 Take a Test fatima carrillo -Mozilla Firefox https://www.mathxl.com/Student/playerTest.aspx?testld 145256810&centerwin; yes Math 1316. Fall 2016 fatima carrillo 19/16 5 Test Chapter 5 Test, Sections 5.1 through 5.6 Mme Remaining: 01:46:37 This Question: 1 pt 6 of 15 (1 complete v This Test: 15 pts p Use a grapher to determine which of the following statements completes an identity for cos Sin (X cos X Sin X O A. cos (2x o B. 2 cos (x)-1 O C. COS X O D. 4 co 4 sin(x) olut s t Ow Click to select your answer.

Solution

cos^4 x   - sin^4 x= (cos^2 x + sin ^2 x)(cos^2x-sin^2x)

                       = 1 (cos 2x)=cos 2x