7.26.R

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Question 7 of 20 (5 points) Back Question 7 V Simplify. COS COS 5x ) - sin (I sin 5 1 = 6Question 8 of 20 (5 points) ' 0 Back True or False? 2 cos (a + 19) cos (a b) = sin a 0052 b is an identity. 0 True 0 False Question 9 of 20 (5 points) True or False? 2 sin (a + b) sin (a b) = cos2 b sin a is an identity. 0 True 0 False Question 10 of 20 (5 points) Qu: Find all solutions to sin (x + %) + sin (x %) l = 0 on [0, 27:). Enter the answer in terms afar, as needed. Do not enter a decimal approximation. Instructions for entering it. x = This question accepts lists of numbers or formulas separated by semicolons. E.g. "2; 4; 6" or "x+l; x-l". The order of the list doesnt matter but be sure to separate the terms with semicolons. Question 11 of 20 (5 points) Use a double-angle formula to evaluate the expression. case) = E Week 26: The Sum, Difference, Double-Angle, Half-Angle, and Power-Reducing Form Question 6 of 20 (5 points) Back Questio Simplify. cos 290 cos 10 - sin 290 sin 100 =