计算:若m/n=2/5,则m+n/n-m=?可否各位兄台给个过程.
若(m-2n)/(2m+n)=3,则[3(m-2n)/(2m+n)-(m-2n)/[2(2m+n)] - {9(m-2n
若2m-3n=5,则(2m+3n)²=?过程,谢谢!
若m、n互为相反数,则(5m-3n)-(2m-6n)=
已知3m=2n,则m/(m+n)+n/(m-n)-n^2/(m^2-n^2)=?
计算(m+2n/n-m)-(n/m-n)+(2m/n-m)要过程
已知m/n=5、,求(m/(m+n))+(m/(m-n))-(n^2/(m^3-n^2))
若m²+n²=10,且m-n=2,则m+n= 求解题过程
若2m-n/m+2n=5,求3(2m-n)/m+2n-m+2n/2m-n+3的值
如果m和n互为相反数,则m+2m+3m+4m+5m+5n+4n+3n+2n+n=
先化简再计算:(m+n)2-4 (m+n)(m-n)+3(m-n)2,其中m=5,n=-45
计算:(2m+3n)(m-2n)=_____________________
初一计算:(m+5n)(m-n)-6(m+2n)(n-3n)?