A triangle has sides A, B, and C. Sides A and B are of lengths #9# and #12#, respectively, and the angle between A and B is #pi/3#. What is the length of side C?
1 Answer
Apr 1, 2016
Explanation:
You use the Cosine rule for this
Note that
For the notation of this question and my diagram.
Cosine rule
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Comment:
I always understood that the standard practice of labelling was that capital letters were used for the vertices (angles) and that small letters were used for the sides.