SOLUTION: prove each identity, SHOW WORK
a. cos(2(3.14)-A)=cos A
b. sin((3(3.14)/2)-A)=-cosA
c. use the identity for sin(A+B) to prove the identity sin2A=2sinAcosA
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Question 199298This question is from textbook
: prove each identity, SHOW WORK
a. cos(2(3.14)-A)=cos A
b. sin((3(3.14)/2)-A)=-cosA
c. use the identity for sin(A+B) to prove the identity sin2A=2sinAcosA
This question is from textbook
Answer by jim_thompson5910(35256) (Show Source): You can put this solution on YOUR website!
I'll do the first one to get you started. Note: I'll use for 3.14
Start with the given equation.
Expand
Evaluate the cosine of to get 1. Evaluate the sine of to get 0
Multiply
Simplify
So this verifies the identity.
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