SOLUTION: Prove the identity: sin(A)·tan(A) + cos(A) = sec(A)

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Question 612445: Prove the identity:
sin(A)·tan(A) + cos(A) = sec(A)
Answer by Edwin McCravy(20060) About Me  (Show Source):
You can put this solution on YOUR website!
Prove the identity:
sin(A)·tan(A) + cos(A) = sec(A)
Use tan(A) = sin%28A%29%2Fcos%28A%29

sin(A)·sin%28A%29%2Fcos%28A%29 + cos(A)

sin%5E2%28A%29%2Fcos%28A%29 + cos(A)

Get an LCD of cos(A)

sin%5E2%28A%29%2Fcos%28A%29 + cos%5E2%28A%29%2Fcos%28A%29

%28+sin%5E2%28A%29%2Bcos%5E2%28A%29%29%2Fcos%28A%29

1%2Fcos%28A%29

sec(A)

Edwin