Chapter Twenty-Two: The Facebook Swotvac (~jinghan)
Back in first year when one young Jinghan was struggling with a question on a physics past paper. Within minutes she had created a facebook group titled: “Help Me With Physics” and posted “2008 past exam, question 8, how do you do it?!”
And that’s how it all started…
“Arg.” I throw my pen at my exercise book in the hope that it will make the integral evaluate itself. It doesn’t. I’m in stalemate. I can’t move on to the next question until I figure this one out (because I have no doubt that if I ignore this question it will be destined to pop up on the exam) The more time I spend on it the more I am dumbfounded by where I went wrong.
It’s been five minutes, and I’ve had enough, I throw open my computer and log in to facebook…
D: “harmless” looking integral defeats Jinghan, help!
0 to 2π :: ∫1/(3+sinθ+cosθ)
Welcome to our facebook group: Complex Analysis HELP Space.
If you had walked into my Complex Analysis class in the second last class of semester you would have seen this on the chalk board:
It was only later that I reflected on the ironic clash of old and new technology in the act of putting a fb link on a chalkboard. I only had time to do it at the start of one lecture and add my friends from the class. But by the time swotvac started the group had grown to 40 members.
A__ L__: help! – three people like this
N__ S__: i^2=-1 – seven people like this
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M__ P__: With regard to practice class 6, question 17 c), could anyone please explain to me why you can’t use the fundamental theorem of calculus? Wouldn’t the antiderivative be F(z)=ln(z-a) and isn’t that analytic on C{a}?
D__ D__: Remember log is not well-defined on the complex plane, so we have to choose a branch to make it a function. Once we’ve done that, there must be a line of discontinuity (branch cut, see the picture on Alex’s website), so log(z-a) isn’t analytic on C{a}.
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L__ P__: If any of you are confused about what uniform convergence is, I found this video helpful. (He starts giving the definiting at 4:30) http://www.youtube.com/watch?v=r9J6lDkqR6o
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A__ L__: group study sesh on friday? anyone up for it? –one person likes this
R__ B__: yes! –one person likes this
B__ M__: make an event!
D__ D__: sounds good!
A__ L__: where shall we have it?
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After a day pondering maths on a Friday, I come home to – yes – more maths to study. At least I found someone at the study session who knew how to do that integral that was harassing me in the morning. But maybe I should turn on my computer incase I need it later… Maybe I should log on to fb incase… uh incase!
Jinghan: D: “harmless” looking integral defeats Jinghan, help!
0 to 2π :: ∫1/(3+sinθ+cosθ)N__ S__: It’s just the same as any other trig integral, with a little more manipulation required.
Jinghan: haha okay i realised my problem: instead of organising it by powers of z and factoring, I organised the denominator by real and imaginary parts… which is pointless and stupid because z is complex xD
M__ M__: So that’s what I was doing wrong as well… : P
Jinghan: *solidarity*
Note from the author: I currently also have a group called Probability HELP Space for my other maths subject. 60 members activity expected to grow when its 1 week before exam. If anyone else feels like making a fb group for their subject, go ahead! This idea is open for expansion! So long as I get all the royalties… oh wait it’s non-for-profit.