SOLUTION: Cos(60-A)+sin(30-A)/cos(30-A) -sin(60-A)=cotA

Work with the left side:

Use cos(a-b) = cos(a)cos(b) + sin(a)sin(b)
and sin(a-b) = sin(a)cos(b) - cos(a)sin(b)



Remove parentheses.  Be careful to make sign change on 
last term of denominator.



Use the fact that  and 










  Use 



Edwin