Posted by Oscar on Wednesday, February 6, 2013 at 9:24pm.
cosØ>0 tells me Ø is in either I or IV
tanØ = 3 tells me Ø is in I or III
So Ø must be in the 1st quadrant
tanØ = 3 = 3/1 = opposite/adjacent
so construct your triangle with those sides,
easy to see that the hypotenuse is √10
so cosØ = 1/√10 ----> secØ = √10
and sinØ = 3/√10 ---> cscØ = √10/3