What is #4/(1+ sqrt3)#?
Type into a calculator the following
So you do the denominator first and then the numerator.
If you don't want to use a calculator, then you can find the square root of 3 and then add that to 1.
After that, divide 4 by the sum of that.
While this could be evaluated directly using a calculator, I believe the intent was to simplify by rationalizing the denominator.