SOLUTION: Show that sin(A+B)/cosAcosB = tanA + tan B

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Question 1020745: Show that sin(A+B)/cosAcosB = tanA + tan B
Answer by Cromlix(4381) About Me  (Show Source):
You can put this solution on YOUR website!
Hi there,
sin(A + B) = sinAcosB + cosAsinB
Divide both by cosAcosB
sinAcosB/cosAcosB cancel cosB's top and bottom
= sinA/cosA = tanA
cosAcosB/cosAcosB cancel cosA's top and bottom
= sinB/cosB = tanB
So sin(A+B)/cosAcosB = tanA + tan B
Hope this helps :-)