还有几道题,1.已知x=2,y是绝对值最小的有理数,则代数式4x^2-2xy+2y^2=?2.若x+3=5-y,a,b互为倒
问题描述:
还有几道题,1.已知x=2,y是绝对值最小的有理数,则代数式4x^2-2xy+2y^2=?2.若x+3=5-y,a,b互为倒
1.已知x=2,y是绝对值最小的有理数,则代数式4x^2-2xy+2y^2=?
2.若x+3=5-y,a,b互为倒数,则代数式0.5(x+y)+5ab=?
答
1、x=2,y=0,所以4x^2-2xy+2y^2=4*4-0+0=16
2、x+3=5-y,所以x+y=2;a,b互为倒数,所以ab=1
所以0.5(x+y)+5ab=0.5*2+5*1=6