4m²﹣9分之2mn与2m﹢3分之2m﹣3通分-搜答案-搜狗做题网

因为|m-n-2|大于等于0(mn-1）的2次方大于等于0且|m-n-2|与(mn-1）的2次方互为相反数所以m-n-2=0mn-1=0则m-n=2mn=1(-2mn+2m+3n)-(3mn+2n-2

m/(m-n)-n/(m+n)+2mn/(m²-n²)=[m(m+n)-n(m-n)+2mn]/(m²-n²)=(m²+n²)/(m

3(m^2+mn)-4(mn-2m^2n)+mn=3m²+3mn-4mn+2m²n+mn=3m²+2m²n=m²(3+2n)

“liljw0924”：二个数的分母分别为4m²-9和2m+34m²-9=（2m）²-3²=（2m+3）×（2m-3）它们的公分母是（2m+3）×（2m-3）通

答：mn/(m+n)=2分子分母同除以mn得：1/(1/n+1/m)=21/m+1/n=1/2(3m-5mn+3n)/(-m+3mn-n)分子分母同除以mn得：=(3/n-5+3/m)/(-1/n+3

先合并同类项,得3(m-n)-6mn+9,代入已知数据,有结果27

原式=(3m-n)²分之m(3m-n)=(3m-n)分之m=(3*1-2)分之1=1

4m²-9=(2m+3)(2m-3)所以最简公分母就是4m²-9所以(2m-3)/(2m+3)=(2m-3)²/(4m²-9)

解最简公分母2(x+y)²,∴(x-y)/(2x+2y)=(x+y)(x-y)/2(x+y)²=(x²-y²)/2(x+y)²xy/(x+y)

再答：这个化简一下答案就有了。。。再问：不对你只算了个2m....的值前面还有个条件再答：式子开括号化简完不是m+n-3mn么？那把题目条件带入不就是答案了？再问：我看错了再答：好吧。。。

（2m-n）分之m

2mn/(4m^2-9)(2m-3)/(2m+3)分子分母同时乘(2m-3)=(2m-3)(2m-3)/(2m+3)(2m-3)=(4m^2-12m+9)/(4m^-9)

根据题意绝对值和完全平方非负所以mn-1=0m-n-2=0mn=1m-n=2（-2mn+2m+3n)-(3mn+2n-2m)-(m+4n+mn)=-2mn+2m+3n-3mn-2n+2m-m-4n-m

1是不是题错了?2由题意有F(0)F(1)0,(-5)(a+2-5)=-5（a-3）0,解得a33分别解方程有m=0或m=3,n=0或n=3.因为MN不相等,所以有（1）M=0,N=3,此时原式=4*

3/(2M-N)=3(2M-N)/(2M-N)²2MN/(4M²-4MN+N²)=2MN/(2M-N)²如果不懂,请Hi我,祝学习愉快!

2mn分之4m方—9=n分之2—9=n分之(2-9n)2m—3分之2m+3=3分之(6m-2m-3)=3分之(4m-3)再问：额不好意思啊我不小心手滑打错了应该是2mn分之4m方—9与2m—3分之2m

①2mn/4m^2-9=2mn/[(2m+3)(2m-3)]②2m-3/2m+3=(2m-3)(2m-3)/[(2m+3)(2m-3)]=(2m-3)²/[(2m+3)(2m-3)]③2mn

3(m^2n+mn)-4(mn-2m^2n)+mn.=3m^2n+3mn-4mn+8m^2n+mn.=11m^2n.

m^2/9+2mn/3+n^2=(1/9)(m^2+6mn+9n^2)=(1/9)(m+3n)^2a^2-14ab+49b^2=(a-7b)^216a^4+24a^2b^2+9b^4=(4a^2+3b

先通分,使分母统一为m²-n²,然后化简分子得（m+n）²,再和分母化简得m-n分之m+n.再问：上面的几分之几是个整体，后面的-号是符号，跟前面的不沾边再答：我知道就是