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