先化简,再求值,已知m=2+根号3,求m²-1分之m-1-搜答案-拍题作业网

原式=9-m2+m2-6m-7=-6m+2=-6*1/2+2=-1

2(mn+m)-[-(3n-mn)-m]+mn　　=2mn+2m+3n-mn+m+mn　　=2mn+3m+2n　　=2mn+3(m+n)　　∵m+n=3,mn=-2　　∴2(mn+m)-[-(3n-m

:(m+2)(m-3)+3(m+1)(m-1)-(2m+3)(2m-1)=m²-m-6+3m²-3-(4m²+4m-3)=-5m-6=-5×(-1/5)-6=-5

16m-6m-16m+2-8=-6m-6=0这个不难慢慢展开就做出来了,要动脑筋啊

m²-m分之m²-2m+1=(m-1)²/m(m-1)=(m-1)/m=(92-1)/92=91/92

很简单啊,合并相同的项：原式=-m^3+0m^2-2m=-m^3-2m带入m的值结果1-（-2）=3

由条件,可化简为：4（M+7/2)2=-9(N+4)2所以,M=-7/2然后接下去应该会了吧.

劝自己做

=（m-1)^2+（m-3)(m+3+m-1)=(m^2-2m+1)+(m-3)(2m+2)=3m^2-6m-5=3(m^2-2m)-5=3乘2-5=1㎡=m^2再问：对不对？再答：对呀再问：嗯再答：

(m-1)^2-3(2-5m+3m^2)=m^2-2m+1-6+15m-9m^2=-8m^2+13m-5=-(8m^2-13m+5)=-(m-1)(8m-5)将m=-1/3代入=-92/9

yarandewo：(3+m)(3-m)+m(m-6)-7=9-m²+m²-6m-7=9-6m-7=2-6m∴当m=1/2时,原式=2-6×(1/2)=2-3=-1

2分之3m-（2分之5m-1）+3(4-m)=2分之3m-2分之5m+1+12-3m=-4m+13=-4*3+13=1

原式＝m/(m+3)-6/(m+3)(m-3)/2/(m-3）=m/(m+3)-3/(m+3)=(m-3)/(m+3).

原式=[(m²-2m+1)/m²]÷[m-1-(m-1)/(m+1)]=[(m-1)²/m²]÷[(m-1)(m+1)/(m+1)-(m-1)/(m+1)]=[

8m(m+n)²-2m(m-n)²=2m(4(m+n)²-(m-n)²)=2m(2m+2n+m-n)(2m+2n-m+n)=2m(3m+n)(3n+m)再把m=

=3m^2-m-m^2+9+2(m^2-2m+1)=-5m+11将m=2代入,得：-10+11=1则原代数式值为1.

m(3m-1)-(m+3)(m-3)-2(m-1)^2=3m^2-m-(m^2-9)-2(m^2-2m+1)=3m^2-m-m^2+9-2m^2+4m-2=3m^2-m^2-2m^2-m+4m-2+9

原式=m+12m(m−1)•4m2(m+1)2-m+1−m+1(m+1)(m−1)=2m(m−1)(m+1)-2(m+1)(m−1)=2m−2(m+1)(m−1)=2m+1，当m=2时，原式=22+1

我怀疑你少一个平方m/(m+3)-6/(m-9)÷2/(m-3)=m/(m+3)-6/(m+3)(m-3)×(m-3)/2=m/(m+3)-3/(m+3)=(m-3)/(m+3)当m=-2时原式=(-

题目是[﹙m²-4m+4﹚/m²-1]÷﹙m-2/m-1+2/m-1﹚?还是m²-4m+﹙4/m²-1÷m﹚-2/m-1+2/m-1?或者是[m²-4