10^m-2n=400

m平方+n平方+2m-6n+10=0（m²+2m+1）+(n²-6n+9)=0(m+1)²+(n-3)²=0m=-1n=3如果本题有什么不明白可以追问,

根据题意得：m-n=2,m-2n+3=3,解得：m=4,n=2,∴m+n+10=16,A=4；4m+6n-1=27,B=3,∴A-B=1,

m-n=2.1/2(m-2n+3)=3求出m和n代人

（1）9^(m-n)=9^m÷9^n=3^(2m)÷(3^n)²=5÷10²=1/20（2）9^(2m-n)=9^(2m)÷9^n=(3^2m)²÷(3^n)²

设m为3(3+2)+(3+2)=10设n为2(3-2)+(3-2)=23333+2222=5555

m2=m+2m3=m(n+2)=mn+2mn2=m+2n3=n(m+2)=mn+2nm2-n2=(n+2)-(m+2)(m+n)(m-n)=-(m-n)m≠n则m-n≠0所以m+n=-1原式=mn+2

10^m=20,10^n=0.2,两式相除就得10^(m-n)=20÷0.2=100=100^2于是m-n=29^m除以3^2n=9m÷9n=9^(m-n)=9^2=81

1/10(2m+n)^2-(3m-n)^2+5m(m-n)=4m^2+4mn+n^2-9m^2+6mn-n^2+5m^2-5mn=5mn=5*1/10*1/5=1/10

m(m+n)(m-n)-m(m+n)^2=m(m+n)[(m-n)-(m+n)]=m(m+n)(-2n)=-2mn(m+n)=-2*(-1/2)*1=1

（5-8）（m-2n）²-（3-2）（m+n）=-3（m-2n）²-（m+n）=-3（-10-2（-6））²-（-10-6）=-3×2²+16=-12+16=4

(m-2n)/(2m+n)=3m-2n=6m+3n5m+5n=0m=-n[3(m-2n)/(2m+n)-(m-2n)/[2(2m+n)]-{9(m-2n)/[4(2m+n)]}=[3(-n-2n)/(

原式=(m^2-6m+9)+(n^2+10n+25)=(m-3)^2+(n+5)^2m=3n=-5m-n=8努力学习吧

m/(m+n)+n/(m-n)-n^2/(m^2-n^2)=[m(m-n)+n(m+n)-n^2]/(m^2-n^2)=m^2/(m^2-n^2)=1/(1-(n/m)^2)=1/(1-(3/2)^2

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)

m^2+n^2=(m+n)^2-2mn=10^2-2x24=100-48=52(m-n)^2=(m+n)^2-4mn=10^2-4x24=100-96=4

设m=ta,n=tb=>tb|(2ta-1)=>t|(2ta-1)=>t|1=>t=1所以m,n互素2m=un+1,2n=vm+1相减得(2+v)*m=(2+u)*n由于m,n互素所以m=2+u,n=

=(m^2-n^2)(-m^2-n^2)-(4m^2-n^2)(4m^2+n^2)=-(m^4-n^4)-(16m^4-n^4)=-（1^4-（-2)^4）-(16*1^4-(-2)^4)=15

m=n(n-1)/2

(2m+n)的平方-(3m-n)的平方+5m(m-n)=4m^2+4mn+n^2-(9m^2-6mn+n^2)+5m^2-5mn=5mn=5*1/10*1/5=1/10

2x+n/m=m/n-(m/n+n/m)x(m/n+n/m+2)x=m/n-n/m﹙m+n﹚²x／﹙mn﹚=﹙m+n)(m-n)／﹙mn﹚∵m+n不等于0∴x=(m-n)／﹙m+n﹚