Answers

2015-01-29T12:17:39+08:00
The branch of mathematics dealing with the relations of the sides and angles of triangles and with the relevant functions of any angles.

tan (a+b)= tan (a) + tan (b)
                1- tan (a)tan (b)

tan (a-b)=tan (a) - tan (b)
              1+ tan (a)tan(b)
                     
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