It is true because 2log100 does not = 0

再看看昔人爺提供的連結，若htf看得明白，其中
問題都應搞清楚啦。知道log1/log1 = 0/0的標準
名稱是indeterminate(不確定)，而不是meaning-
less。勤力一點的，更可從知道為什麼0/0是
indeterminate，x/0 (x<>0)卻是undefined。

這是口語英語，可不follow文法。

2log100/2log100
=2/2
=1
log100 = 2, therefore 2log100/2log100 = 4/4 = 1

x/0 can be infinitive too, isn't it?
Do you mean "infinity" ? ("Infinitive" is 不定詞.)
Well, here is a page that might answer your question:
http://www.mathforum.com/dr.math/problems/white.9.5.96.html

Xiren, how can you find these math question web site?
Try my favorite search engine -- Alta Vista:
http://www.altavista.com/
If you know what you're looking for (i.e. the keywords), you can almost find any information you need from the web in no time.

No offence, but if you don't understand this, you're not gonna do
really well in math. It's my exp teaching math.
IMHO, not everyone has to be good at math, but math is a good tool that helps people think or learn how to think.

BTW, should it be misconception towards, of, or what?
"About" seems to be more frequently used in this case.

"I think that the problem is not 中三 but *instead* your misconception of 約掉."
To me, this sentence is not any different from the other one. I think that the only purpose which "instead" serves here is to emphasize "your misconception...". Since "instead", an adverb, does not modify that phrase meaningly, it can be omitted.

只是借此藉口來遮羞吧
我並不覺得問這問題有啥羞恥。事實上我認為這是
個好問題，因為它讓大家有機會動動腦筋，相信也
幫助澄清部分朋友的觀念。如果你去看了我推薦的
網頁，會發現許多人也有類似的疑問。我認為最重
要的不是知道答案是什麼，而是理解答案背後的意
義，否則今後還可能問類似的問題。問問題並不可
恥，問重複的問題才可恥，因為那表示一直沒搞懂。
在下以為懶蛇和余非老頭的評語未免太嚴苛了。

Here's what I was trying to say:

YCP had already made it very clear (and I had admitted) that using L'Hopital rule is NOT a correct approach. So, that should really be the end of that little L'Hopital twist I created. I'm not exactly sure why Lazy Snake went through all the trouble to prove once more that using L'Hopital isn't a valid approach(this is what I thought he was trying to do. However, I do believe to some extend that he might have been trying to say something else--I have to admit that I have trouble interpreting people's punctuations(among many other things)--and if that's case, I dare not comment). Of course, I don't think he did it because he wanted to show mathmatical ablilities. If that't what you think I thought, well, I don't know what to say. That's why I said he might want to consider reading other people's messages first before posting his own. I mean, if something has already been said, and you can't add anything more to it, why repeat it? Maybe he just did this out of his experience teaching math: Repeat it as many times as necessary until the #$^$^#@ understands.

.......

Well, I got to admit that it certainly worked in my case.....and as a bonus, I'm beginning to understand a lot of things I didn't understand only a few days ago.

YCP had already made it very clear (and I had admitted) that using
L'Hopital rule is NOT a correct approach.
Well, I have to disagree. Your approach was not incorrect, but incomplete. Mr. "I'm not an old man" made it complete:
log 1 / log 1 may be represented as
limit_(x -> 1) [log x / log (2-x)] (= -1)
i.e. not necessarily
limit_(x -> 1) [log x / log x] (= 1)
so ... (log1/log1 is indeterminate)

I think that the above is the most important statement in the entire thread so far. It revealed why log1/log1 should be indeterminate, and "I'm not an old man" later used L'Hopital's Rule to prove that (along with Lazy Snake's attempt, or it could have been yours.) If you didn't get this..., well, would you like some more repetitions? ^_^

區區在下認為直說「分母是 0 就是undefined」
也不能消解 htf 的疑問﹐所以在下企圖用另
一個角度解釋：分子分母能「約掉」只因為這
個分數的值是 1。所以 log1/log1 = 1log1/1log1
= 1/1 這算式已暗示 log1/log1 = 1﹐和直接
寫 log1/log1 = 1 並無分別。換句話說，這
個所謂「另一個角度」只是一個虛像。

htf 看了這個﹐一面說區區在下也很有道理﹐
一面卻以 log100/log100 類比﹐由此可知他
當時根本不明白其中道理。這也不相干﹐只是
那一句「我只是中三而已」的辯解(後來方知
不是htf 寫)令區區在下有點不滿﹐因為區區
在下覺得這是不長進､不負責任的懦夫話。於
是就回應道﹕I think that the problem is
not 中三 but the misconception towards
約掉。這是針對「分子分母相約」的問題﹐何
苛刻之有﹖(當然﹐區區在下出言無禮﹐不留
情面應是眾所周知的。)
要是區區在下真來苛刻﹐單是一句「只是借此
藉口來遮羞」就該罵過狗血淋頭啦﹗

一、已知：任何數與零相乘，結果為零。
　　因此 1x0=2x0=3x0=4x0=...=0
　　0/0=(1x0)/(2x0)=(3x0)/(4x0)...

It's really interesting going back and read all the messages again. Grammatical errors are just minor matters compared to the inconsistencies that occur in people's messages.

Anyway, I'm going to pull what I usually pull in this kind of situations: who cares?!

I was 100 ure that this YCP was "I'm not an old man" as soon as I read this sentence: Your 同樣道理 is not logical. ^_^

To be honest, I was not sure. Sure, "I'm not an old man" likes to say stuff like that and has all the logical reasons for doing so, but there are just too many similarities between "old man" and !"old man".

From my perspective, there is nothing wrong about doubting or challenging what we were told/taught. That's what differentiates a great philosopher/inventor/scientist from an ordinary person. "Learn" and "know" are not enough; "think" and "understand" are more important! htf, keep up the good thinking!

just wanted to encourage htf to take a more in depth study in math.
Sorry that I misunderstood your messages, but I felt that this message looked rather intimidating than helpful...
If you think they can be cancelled out, then answer me:
sin 0 / sin 0 = ?

Also, I didn't realize that the following was supposed to be an encouragement instead of a dissuasion:
No offence, but if you don't understand this, you're not gonna do really well in math.

limit(x->1)(log x/log(2-x))
= limit(x->1) ((1/x)*(log e)) / (-(1/(2-x))*(log e)) (L'Hopital)

substitute x=1,

= (1)/(-1)=-1

(There's probably an easier approach.)

在下覺得這是 htf 邏輯推理有問題﹐而不是
程度的問題﹐理由已說過許多遍。
在下也說過？遍：閣下覺得 htf 邏輯推理錯誤，是
基於「他知道 0/0= 無意義」的假設，而由他的回
應即可確定這個假設是錯的，因此根本沒有所謂邏
輯的問題。何況，即使真有其事，難道指責人家邏
輯有問題，就能令人理解問題嗎？

當一個人一邊說自己已明白一個道理時﹐另一
邊卻表現自己不明白該道理。重複﹐再「明白」﹐
再「不明白」。余非老頭只好直截了當的說這
個人錯了﹐所錯者為何。

依小可看，htf 知道 0/0 是 meaningless，但被
其他人的留言搞亂了頭腦，於是忘記了 0/0 不能
約掉喇。余非老頭爺看見了「只有中三程度」的
「遮羞」話後反應確實略為過激，稍為苛刻了半點
囉；而昔人爺亦稍有過份維護 htf 之嫌。