已知x+y=1,求0.5x²+0.5xy+0.5y的值

问题描述:

已知x+y=1,求0.5x²+0.5xy+0.5y的值

0.5x²+0.5xy+0.5y
=0.5(x²+xy+y)
=0.5(x(x+y)+y)
=0.5(x+y)
=0.5