Answer :
just use FOIL (First, Outer, Inner, Last).
( √2 - √3 ) X ( √2 - √3 )
First: √2 X √2 = 2
Outer: √2 X -√3 = -√6
Inner: -√3 X √2 = -√6
Last: -√3 X -√3 = 3
and then add them together.
2 - √6 - √6 + 3
5 - 2(√6)
The answer is 5 - 2(√6) .
