How do you simplify #(sqrt5+2sqrt2)/(4-sqrt5)#?
Use the conjugate of the denominator to turn it into a whole number. Details below...
The first thing you want to do is eliminate the radical expression in the denominator. To do this, multiply top and bottom by the conjugate of the denominator, namely
Use the FOIL method to multiply top and bottom
I think that is all you can do!