SOLUTION: Sin (A+B)/Sin A.SinB=Cot A + Cot B

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Question 1078303: Sin (A+B)/Sin A.SinB=Cot A + Cot B
Answer by ikleyn(52887) About Me  (Show Source):
You can put this solution on YOUR website!
.
When posting this problem, your first words must be
"Please help me prove this identity . . . " 

1.  Your first step is to write both sides in terms of sin and cos.

    For it, use the DEFINITION of cot.


2.  Then write the right side with the common denominator.


3.  Then cancel the common denominator.


4.  After that, use the addition formula for sine.


    And you, finally, complete the proof of this identity.