



 
To verify the identity \[\frac{\sin S}{1 + \cos A} + \frac{1 + \cos A}{\sin A} = 2 \csc A\] I would start by writing $\csc A$ as $\large \frac{1}{\sin A}.$ Next multiply the numerator and denominator of the first fraction on the left side by $ 1  \cos A$ and simplify. This will result in a denominator of $\sin^2 A.$ If you then multiply the numerator and denominator of the second fraction on the left side by $\sin A$ the two fractions will have the same denominator. Add the fractions and simplify. Penny  


Math Central is supported by the University of Regina and The Pacific Institute for the Mathematical Sciences. 