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jackAt the weekend, I watched Mean Girls. Near the end, there's a scene where the protagonist has to answer a bonus sudden-death question in an inter-school math quiz, lim x->0 of log(1-x)-sin(x) over 1-cos2(x).
I followed up by googling the limit she had to find, and lo, unsurprisingly, there were people discussing it. There's just something weird about that.
In fact, it was pretty well chosen. It was on the screen for only a second, and they could have put gibberish there, but it was correct, and something you *could* solve in your head if you were on the ball.
Of course, I'm way out of practice, which is rather depressing. I remember lots of things, but to use them I need to write it all out from scratch, there's nothing I can do confidently.
As it happens, I nearly got this right, but unsurprisingly messed up the taylor expansions. I thought they'd used "has no limit" for "limit of infinity", but no, it's right, the sign is different above and below, so there is definitely no limit.
But then it occurred to me that that was probably contentious in itself. If f(x)->oo, devoid of context, I'd say nothing but "limit of infinity". But someone would say, it has no limit. After all, there's no actual number in the domain which is the limit. But in all applications I'm familiar with, knowing that tends to inf is useful.
Would anyone go with the "no limit" answer?
I followed up by googling the limit she had to find, and lo, unsurprisingly, there were people discussing it. There's just something weird about that.
In fact, it was pretty well chosen. It was on the screen for only a second, and they could have put gibberish there, but it was correct, and something you *could* solve in your head if you were on the ball.
Of course, I'm way out of practice, which is rather depressing. I remember lots of things, but to use them I need to write it all out from scratch, there's nothing I can do confidently.
As it happens, I nearly got this right, but unsurprisingly messed up the taylor expansions. I thought they'd used "has no limit" for "limit of infinity", but no, it's right, the sign is different above and below, so there is definitely no limit.
But then it occurred to me that that was probably contentious in itself. If f(x)->oo, devoid of context, I'd say nothing but "limit of infinity". But someone would say, it has no limit. After all, there's no actual number in the domain which is the limit. But in all applications I'm familiar with, knowing that tends to inf is useful.
Would anyone go with the "no limit" answer?
no subject
Date: 2007-06-05 03:48 pm (UTC)I now have an urge to say something along the lines of "No no. No no, no no. No no, no no, no no there's no limit" just so I have a chance of feeding someone else the earworm you've just given me.
no subject
Date: 2007-06-05 03:57 pm (UTC)no subject
Date: 2007-06-05 04:14 pm (UTC)http://www.youtube.com/watch?v=MjqKHYaf8EQ
(I'm afraid that's what went through my head when I first saw your post too :-)
no subject
Date: 2007-06-05 04:15 pm (UTC)no subject
Date: 2007-06-05 04:13 pm (UTC)Truly cringe-worthy.
Truly cringe-worthy.
Date: 2007-06-05 04:14 pm (UTC)Re: Truly cringe-worthy.
Date: 2007-06-05 04:19 pm (UTC)* The company changed names at least once a year for a while.
Re: Truly cringe-worthy.
Date: 2007-06-11 01:26 pm (UTC)no subject
Date: 2007-06-05 05:34 pm (UTC)