已知m,n满足(m-2)²+|½n+1|=0.求[(3m-n)²-(2m+n)²+5m(m-n)]÷5m的值
问题描述:
已知m,n满足(m-2)²+|½n+1|=0.求[(3m-n)²-(2m+n)²+5m(m-n)]÷5m的值
答
已知m,n满足(m-2)²+|½n+1|=0所以m-2=0,½n+1=0所以m=2,n=-2所以[(3m-n)²-(2m+n)²+5m(m-n)]÷5m=[(3*2+2)²-(2*2-2)²+5*2(2+2)]÷(5*2)=(64-4+40)÷10=10