Question

已知x=根号5+根号3 ,y=根号5-根号3,求x²-xy+y²

Answer 1

x=√5+√3 y=√5-√3

x-y=2√3 xy=2

x^2-xy+y^2

=(x-y)^2+xy

=(2√3)^2+2

=12+2

=14