Question

How do you prove the following?

`cotx+coty=(cscxcscy)/csc(x+y)`

Answer 1

`LHS=cotx+coty`

`=cosx/sinx+cosy/siny`

`=(sinxcosy+cosxsiny)/(sinxsiny)`

`=sin(x+y)/(sinxsiny)`

`=(1/csc(x+y))/(1/(cscxcscy))=(cscxcscy)/(csc(x+y))=RHS`