杭州交通信息网dh追随者怎么获得:数学高手帮帮忙啊！
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2A3B-1/2A3B-A2B+1/2A2B-AB2
2.选择题
1.(M4-16N4)÷（M2+4N2）÷（2N-M）的值为:
A.m-2n B.m+2n C.-m-2n D.-m+2n
3.已知A=3M2-2N2+MN,B=5MN-6M2-9N2,并且A-B+3C=0.求多项式C
4.(1/2+1/3+……+1/2000+1/2001)(1+1/2+1/3+……+1/2000)-(1+1/2+1/3+……+1/2001)(1/2+1/3+……1/2000)
5.以知a2+a=1/3,求6a4+15a3+10a2的值.
1.合并同类项
2A3B-1/2A3B-A2B+1/2A2B-AB2
2.选择题
1.(M4-16N4)÷（M2+4N2）÷（2N-M）的值为:
A.m-2n B.m+2n C.-m-2n D.-m+2n
3.已知A=3M2-2N2+MN ,B=5MN-6M2-9N2,并且A-B+3C=0.求多项式C
4.(1/2+1/3+……+1/2000+1/2001)(1+1/2+1/3+……+1/2000)-(1+1/2+1/3+……+1/2001)(1/2+1/3+……1/2000)
5.以知a2+a=1/3,求6a4+15a3+10a2的值.
所有字母后的数字表示为平方.为什么百度知道打不到平方啊????我在WORD已经编辑好的了,到这里却不可以,悲哀悲哀.
1.2A^3B-1/2A^3B-A^2B+1/2A^2B-AB^2
= 3/2 A^3B -1/2 A^2B - AB^2
------------------------
2.C
-----------------------
3.
A-B+3C=0
--> C=(B-A)/3
A=3M^2-2N^2+MN,B=5MN-6M^2-9N^2
C=(4MN-9M^2--7N^2)/3
-------------------------
4.设a = 1/2+1/3+……1/2000,
则(1/2+1/3+……+1/2000+1/2001)(1+1/2+1/3+……+1/2000)-(1+1/2+1/3+……+1/2001)(1/2+1/3+……1/2000)
= (a+1/2001)*(a+1)-(a+1+1/2001)*a
= (a+1/2001)*(a+1)-(a+1/2001)*a -a
= (a+1/2001)-a
= 1/2001
---------------------
5.
6a^4+15a^3+10a^2
=6a^4+6a^3+9a^3+10a^2
=6a^2(a^2+a)+9a^3+10a^2
=2a^2+9a^3+10a^2
=9a^3+9a^2+3a^2
=9a(a^2+a)+3a^2
=3a+3a^2
=3(a^2+a)
=1
1=2/3A^3B-1/2A^2B-Ab^2
2、C.-m-2n
3、C=1/3(B-A)=-3m^2-7/3N^2+4/3MN
4.设a = 1/2+1/3+……1/2000,
则(1/2+1/3+……+1/2000+1/2001)(1+1/2+1/3+……+1/2000)-(1+1/2+1/3+……+1/2001)(1/2+1/3+……1/2000)
= (a+1/2001)*(a+1)-(a+1+1/2001)*a
= (a+1/2001)*(a+1)-(a+1/2001)*a -a
= (a+1/2001)-a
= 1/2001
5.
6a^4+15a^3+10a^2
=6a^4+6a^3+9a^3+10a^2
=6a^2(a^2+a)+9a^3+10a^2
=2a^2+9a^3+10a^2
=9a^3+9a^2+3a^2
=9a(a^2+a)+3a^2
=3a+3a^2
=3(a^2+a)
=1
第5题：等于-7/18
计算方法是：把a2=1/3-a代入求的值里面就可以了。
A的二次方可标为A^2
晕...那么多...眼睛都花了...我老了脑子不好用...不好意识帮不了你啊..........
小朋友，不会把幂上标呀， 还真的帮不了你。