|贴子

2005-12-02
Help~数学吧
1. 若方程7x^2- (k+13)x+k^2-k+2=0有2个实根a,b,且满足0<a<1<b<2,则k的取...
2005-11-22
哪位高人，抽空看看吧~高中数学吧
1. (x+3y)^n展开式系数和等于(7a+b) ^10展开式二项系数和，则n=52. 过原点O的直线与...
2005-11-21
有答案，但要过程（２）高中数学吧
6. 在数列{an}中,若a1=1,a(n+1)=an+2n则an=n^2-n+17. 数列{an},满足a1=2,n≥2时,an=a...
2005-11-21
有答案，但要过程～高中数学吧
1. 若方程7x^2- (k+13)x+k^2-k+2=0有2个实根a,b,且满足0<a<1<b<2,则k的取...
2005-11-21
有答案，但要过程（１）高中数学吧
1. 若方程7x^2- (k+13)x+k^2-k+2=0有2个实根a,b,且满足0<a<1<b<2,则k的取...
2005-11-21
有答案，但要过程（１）高中数学吧
1. 若方程7x^2- (k+13)x+k^2-k+2=0有2个实根a,b,且满足0<a<1<b<2,则k的取...
2005-11-21
帮忙看一下（要过程）数学吧
１. 若等比数列的前10项和是10,前30 项和是70,则前20项和是30２. 在数列{an}中,若a1...
2005-11-21
好难啊～数学吧
1. 若方程7x^2- (k+13)x+k^2-k+2=0有2个实根a,b,且满足0<a<1<b<2,则k的取...
2005-11-21
帮忙啊～又遇上麻烦了英语大吧车吧
1. It seems that nobody knows what consequence will (　） this.A rise from B ari...
2005-11-09
莫莫sisi 一定要加我啊～英语大吧车吧
♡♡♡♡♡♡♡♡♡♡♡ ...
2005-11-05
有选择题请教，请帮忙解答一下，谢谢！！！（说明理...英语大吧车吧
1.The results of his study have turned out to be more satisfafctory than ( )A ...
2005-10-18
帮忙解答~谢谢！（说明理由）高中英语吧
1.(A)people are sending information by E-mail every day.A Several million B Ma...
2005-10-09
选择题~谢谢。。。高中英语吧
1.I believe(D)very largely due to calessness.A this accident B this accident b...
2005-09-24
好象搞混了英语吧
Mr.Reed made up his mind to devote all he had to(setting up)some schools for poo...
2005-09-24
选择题英语吧
This is the only work(B)at the moment.(D哪错?)A when I can doB that I can do...
2005-09-24
请教一下～谢谢英语吧
Is this the dimond ring (B) you wanted to buy fot your wife the other day?A wh...
2005-09-24
难住了呀~帮忙解答*_*高中数学吧
复数Z=3+3*3^0.5i+m,m∈C且(m+3) / (m-3)为纯虚数，求∣Z∣范围 key:3≤Z≤9（提示解得∣m...
2005-09-24
高人亮个相吧~谢谢高中数学吧
设a,b,c分别为△ABC的边BC，CA，AB的长，且a^2+b^2=mc^2（m为常数），若ctgC/(ctgA+ctg...
2005-09-24
极限题，谢谢！高中数学吧
杨辉三角中直线AB上方的数组成数列1，3，6，10 ……数列前n项和S(n)，则lim n^3/S(n)=6 ...
2005-09-24
关于三角函数的，题目好复杂啊~高中数学吧
Sin(∏cosa)=cos(∏sina) 则sin2a= (3/4 or -3/4) Why?