Question #366e9
2 Answers
Feb 2, 2018
Explanation:
start with the sum and difference formulas for sine:
add them together to get:
For this problem, let
Feb 2, 2018
Explanation:
#"using the "color(blue)"product to sum formula"#
#•color(white)(x)2sinAcosB=sin(A+B)+sin(A-B)#
#"here "A=7theta" and "B=3theta#
#rArr2sin7thetacos3theta#
#=sin(7theta+3theta)+sin(7theta-3theta)#
#=sin10theta+sin4theta#