十月梦队数学讨论专帖，请NN多多支持！！

joice

My eyes are fine too. Thanks to Gmat.
of course, people envy my eyes too, but i don't know why no one calls me 数学老师?

joice

晴mm,
眼痛头痛腰痛的

重建 天堂 with him  is not a easy job, you take good care of yourself.

joice

271). 有个方差的问题，A,B两个数列，问A的方差大于B吗 1， A的算术平均数>B,  2， A的中数>B,
参考答案：: D   思路: 该题心里没有底。

这题应该是E吧

joice : Agree E.

D each can answer is wrong.

[此贴子已经被作者于2003-10-1 1:02:51编辑过]

joice

290)、(a,b)是x+y=4上的点，问(a,b)是否在第一象限： (1)y>2  (2)x>0 答案：B

这题应该是C吧

The answer B is wrong.
2). x > 0, (a, b) can be a point either at第一象限 or 第 4象限. so 2) alone can't answer the Q.

agree C.

joice

眼痛头痛腰痛的,

I think you didn't rest well. try eye exercises. take care.

祈晴坊主

以下是引用joice在2003-10-1 0:28:00的发言：
My eyes are fine too. Thanks to Gmat.
of course, people envy my eyes too, but i don't know why no one calls me 数学老师?

good and petty math teacher:

how did GMAT help you to relief your eyes ache?

share sth to me !

i am suffering a lot

祈晴坊主

以下是引用joice在2003-10-1 0:37:00的发言：
晴mm,
眼痛头痛腰痛的

重建 天堂 with him  is not a easy job, you take good care of yourself.

yeah,of course it's a tough job

hehe

we all have courage and confidence

but it's seems that's not enough,  crying ~~~~~~~~~~

btw:what is eyes exerise

remeo

以下是引用hz在2003-9-30 23:14:00的发言：
好象不能这么理解，这只是根据答案倒推的。只能说题目中未把问题表述清楚。

想请问一下，正态分布中，落在m-d与m+d之间的概率是0，683吗？那《m-2d,m+2d》
《m-3d,m+3d》之间呢？这有什么计算公式吗？此题的考点究竟是什么呢？

joice

MM, I don't use eye drops.  i never trust medicine.
I played game. although last year' new yr eve, I had my best conquer ever, my eyes were permanently  damaged.
eye exercise is eye massage. several times everyday. hope it works well on you.

祈晴坊主

以下是引用joice在2003-10-1 22:49:00的发言：
MM, I don't use eye drops.  i never trust medicine.
I played game. although last year' new yr eve, I had my best conquer ever, my eyes were permanently  damaged.
eye exercise is eye massage. several times everyday. hope it works well on you.

what is eye massage?

is it just" open ,close,then open ,close,
or see up ,see down ,see left .see right"?