Question

求一数学题的解,整式的运算-完全平方公式,求详解

Answer 1

x(x-1)-(x²-y)=-2

x²-x-x²+y=-2

x-y=2

(x²+y²)/2-xy

=½﹙x²-2xy＋y²﹚

=½﹙x－y﹚²

=½×2²

=2