Kurwa
Member
lol im glad this bothers you guys haha..
suck shit
suck shit
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09'ers so you think you can do maths? (2 Viewers)
- Thread starter Kurwa
- Start date
tommykins
i am number -e^i*pi
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There is an error in the question. There should be a negative sign somewhere. You can check this by binomial expansion and putting the real numbers in the calculator.
Since you really want this question answered (I just outlined the main steps, you can fill in the gaps which shouldn't be too difficult):
^n + (1-i\tan x)^n \\\\= \dfrac{1}{\cos^nx}\left (\cos nx + i\sin nx + \cos nx - i\sin nx \right)\\\\= 2\sec^n x \cos nx\\\\$Note that $ Re((1+i\tan x)^n)= Re((1-i\tan x)^n)\\$Let $ x = \dfrac{\pi}{8} $ and $ n = 8\\\\2Re((1+i\tan \dfrac{\pi}{8})^8) = 2\sec^8\dfrac{\pi}{8}\cos \pi\\\\= \dfrac{-2}{\cos^8\dfrac{\pi}{8}}\\\\= \dfrac{-32}{\left (\cos\dfrac{\pi}{4}+1 \right)^4}\\\\= \dfrac{-32}{\left (\dfrac{1}{\sqrt{2}}+1 \right)^4}\\\\2Re((1+i\tan \dfrac{\pi}{8})^8) = \dfrac{-128}{(1+\sqrt{2})^4}\\\\Re((1+i\tan \dfrac{\pi}{8})^8) = 64(12\sqrt{2}-17))
I don't see how this is any different to the revising games nor do I see how they test "maths"...also please do not make unjustified, assumption-based statements like "you are poor at maths" because that just incites other people to throw insults back at you (unless of course that is your intention)...
Since you really want this question answered (I just outlined the main steps, you can fill in the gaps which shouldn't be too difficult):
I don't see how this is any different to the revising games nor do I see how they test "maths"...also please do not make unjustified, assumption-based statements like "you are poor at maths" because that just incites other people to throw insults back at you (unless of course that is your intention)...
Last edited:
K
khorne
Guest
I think it's a question if you can do maths...the 09'ers seem more than capable...=]
GUSSSSSSSSSSSSS
Active Member
lol good attempt at a thread, but no one can be bothered lol
shuning
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回复: Re: 09'ers so you think you can do maths?
lol....
but that person can be bothered tutoring ppl from st ives and not bothering in this.....
lol....
but that person can be bothered tutoring ppl from st ives and not bothering in this.....
GUSSSSSSSSSSSSS
Active Member
Re: 回复: Re: 09'ers so you think you can do maths?
hehehe....depends on your definition of "tutoring"
shuning
Member
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回复: Re: 回复: Re: 09'ers so you think you can do maths?
lol u said u wanted to be a tutor after the HSC
what kind of definition is that? xD
or did i give u a new definition of tutoring?
lol u said u wanted to be a tutor after the HSC
what kind of definition is that? xD
or did i give u a new definition of tutoring?