Question

(10分）(1)已知x=2-y=2+ 求：x²+xy+y²的值.
(2)已知x=+1,求x+1-的值.

Answer 1

(1)x²+xy+y²
=(x²+2xy+y²)-xy
=(x+y)²-xy
=(2-+2+)²-(2-)(2+)
=16-1=15.

略