3m=5n 2m-3n=1

原式=[m^2+2mn+n^2-3mn+mn-3mn+n^2-5m^2]/2m=[-7m^2+2n^2]/2m=[-7*4+2*1/4]/2*(-2)=[-55/2]/-4=55/8很高兴为您解答,祝

既然是相反数,就是m和n两者加起来为0的,例如-1和1,-2和2就互为相反数,所以这里答案是0咯

m=(-5n-1)/3=-2n+(n-1)/3由于|m|为质数,(n-1)/3必为奇数,进而n-1必为奇数,n必为偶数,又由于|n|为质数,则n=+-2,其中只有-2满足(n-1)/3为整,故n=-2

易知函数f(x)=3^x+6x-1在x＞0时是增函数,因此m随着n的增大而增大,然后就列举计算来求啦,没别的好办法,n=1,m=3+6-1=8＜2000；n=2,m=9+12-1=20＜2000；n=

原式=[m^2+2mn+n^2-3mn+mn-3mn+n^2-5m^2]/2m=[-7m^2+2n^2]/2m=[-7*4+2*1/4]/2*(-2)=[-55/2]/-4=55/8

m-{n-2m+[3m-(6m+3n)+5n]}=m-n+2m-[3m-(6m+3n)+5n]=3m-n-3m+(6m+3n)-5n=-6n+6m+3n=6m-3n

m/(m+n)+m/(m-n)-n²/((m²-n²)=(m²-mn+m²+mn-n²)/(m²-n²)=(2m&sup

则(3m-2n+1)+|5m=2n-n|=0所以(3m-2n+1)=0且|5m=2n-n|=0所以解方程.在(3m-2n+1)=0中3m-2n=-1在|5m=2n-n|=0中5m=n所以把5m=n代入

由题意，得2m−3n＝8m+3n＝−5，解得m=1，n=-2，∴n2m=4．

[(3m+2n)(3m-2n)-(m+2n)(5m-2n)]÷(1/3)m=[9m²-4n²-5m²+2mn-10mn+4n²]÷(1/3)m=[4m²

原式=m/(mn)m/(m-n)-n^2/(m^2-n^2)=(m^2-mnm^2mn)/(m^2-n^2)-n^2/(m^2-n^2)=(2m^2-n^2)/(m^2-n^2)因为m/n=5/3,所

3m=5n+13m-6n=-n+1n=3(2n-m)+1=3(2n-m+1)-2所以可令n=3k+1或者3k-2.

由m/n=5/3,得m=5n/3原式={(m-n)/(m-n)*(m+n)+(m+n)/(m-n)*(m+n)}*n-n平方/(m-n)*(m+n)=2mn/(m平方-n平方）-n平方/(m平方-n平

答：(5m+3n)^2-(m-3n)(25m-3n),其中m=1,n=2=25m²+30mn+9n²-(25m²-3mn-75mn+9n²)=30mn+78mn

等于0

已知m=5n,则原式=(5n/(5n+n))+(5n/(5n-n))-(n^2)/(((5n)^3)-n^2)=(5/6)+(5/4)-[1/(125n-1)]=(25/12)-[1/(125n-1)

4.5*5=4.5+(4.5+1)+(4.5+2)+(4.5+3)+(4.5+4)+4.5+5)=4.5x6+1+2+3+4+5=27+15=42m*8=37.8m*n=m+(m+1)+(m+2)+(

(2m-n)/(m+2n)=5∴(m+2n)/(2m-n)=1/5∴3(2m-n）/m+2n-m+2n/2m-n+3=3×(2m-n)/(m+2n)+(m+2n)/(2m-n)+3=15+1/5+3=

(2m-n)/(m+2n)=5∴(m+2n)/(2m-n)=1/5∴3(2m-n）/m+2n-m+2n/2m-n+3=3×(2m-n)/(m+2n)+(m+2n)/(2m-n)+3=15+1/5+3=

由m/n=5/3,得m=5n/3原式={(m-n)/(m-n)*(m+n)+(m+n)/(m-n)*(m+n)}*n-n平方/(m-n)*(m+n)=2mn/(m平方-n平方）-n平方/(m平方-n平