Mean Girls, original vs. remake: Why was the limit problem changed?

Cafe Society
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1

In both versions of the movie Mean Girls, there’s a climactic moment when the main character, Cady, is at a math competition, on the final question, where the contestants have to determine the value of the limit of an expression. The opponent buzzes in first, and gets it wrong, and then Cady correctly states that the limit does not exist, and wins the competition for her team.

But the problem was subtly changed from the original to the remake. In the original, the problem was \lim_{x \to 0}\frac{\ln(1-x)-\sin(x)}{1-\cos^2(x)}. Near 0, this function behaves like \frac{-2}{x}, and therefore has an asymptote, approaching -\infty on the right and \infty on the left. This is a clear and unambiguous case where the limit does not, in fact, exist.

But in the remake, the problem was \lim_{x \to 0^+}\frac{\ln(1-x)-\sin(x)}{1-\cos^2(x)}. See the difference? There’s a little + sign next to the 0 in the limit, which means that the problem is asking only for the limit as one approaches 0 from the right. The right answer now has some ambiguity to it, depending on how one defines limits at infinity: One might still say that the limit does not exist, but one might also say that the limit is -\infty.

But I can’t figure out why this mistake would be made. The easiest thing to do, of course, would be to use the exact same problem as in the original. If it had gone the other way, with the one-sided limit in the original but not in the remake, then one might suppose that the + sign was accidentally omitted in a typo, by a set person who didn’t realize that it mattered, or it could have been deliberately removed to make it a “cleaner” win at the competition. But it’s the other way around. It’s highly implausible that the + sign would be accidentally added via a typo, and it doesn’t do anything for the story to make the competition win ambiguous. So why the change?

Aside: Someone involved in the creation of the movie clearly knew calculus well, and took care with it. At several points in the movie, the plot calls for a student to get the calculus wrong, and in each case, the mistake made was, in fact, a plausible mistake for a student to actually make.

2

The easiest thing to do is pay someone as little as possible to copy the original without even exercising the minimal level of care needed to ensure the accuracy of the copy.

This guy from Entertainment Weekly says that is an *endemic’ problem in the remake.

3

Well, yes, but like I said, that might account for a dropped plus sign, but it wouldn’t account for one being added. I mean, it could result in a random symbol being added to a random spot in the expression, but it’s exceedingly unlikely that adding a random symbol to a random spot in a math expression would result in something that’s still meaningful.

4

This is a total WAG, but I’m wondering if someone, at some point, thought that the function in question was only defined for x>0, either because they had a brain fart looking at the \ln(x-1) and thought of \ln(x), or because at one point they planned to replace \ln(x-1) with \ln(x) in the problem but the change was never made.

5

I bet it’s because of all of the mathematicians that complained hen the original came out.

6

I’ll bet they’re a real hit at the cocktail parties thrown by all the astronomers who complained when Titanic came out.

7

I mean, of course, \ln(1-x) (but was too late to edit)—which maybe just goes to show how easy such a brain fart could be?

8

I thought Cameron hired an astronomer specifically to get the stars right in Titanic.

9

But he still ended up having to fix one error:

10

I know I’m still pissed about that but not as much as the ending to The Abyss where Ed Harris’ character lives.

Stranger

11

How about the History / folks living in the area pointing out that Lake Wissota (which Jack mentions) didn’t exist until 1917 – years after the Titanic sinking

Brian

12

Did they? I expect that most mathematicians probably didn’t bother to watch it because they weren’t interested in high school drama, but that those who did probably found it to be well above their expectations.

As for the Titanic stars, movies and TV shows almost never get the stars right. I’d never complain about shows that get the stars wrong, because that’s basically every show that ever has a night scene. The only two exceptions I’ve ever seen are Avatar: the Last Airbender (the cartoon one), and Lucifer, and so my response, instead of complaining about the wrong ones, is to praise those two.

13

Neil deGrass Tyson nitpicked the stars in Titanic specifically because a big part of the marketing of the movie was how much effort and money went into historical accuracy. Compared to how the rest of the movie looks, if you look at that original sky shot, it’s a jarring as using a doll instead of a baby.

The kicker is any decent planetarium could have simulated the exact sky at that exact place and time within minutes.