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 Now online (1)dariusgriffin ...and 420 guests Last 5 registered Oplandisks nothingstar N_loop yipe foxtrotromeo Browse members... |
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maybe there IS some mathematical genious here. so, i have prove why lim sinx/x = 1 x-->0 can somebody help me ? |
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yeah. that's proved by calculus. that's all i can remember. did it for my leaving cert though. piss easy stylez |
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sorry, what i meant to write was: |
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it's kinda easy, cause sin(x) = x - x^3/3! + x^5/5! -... for x newt to 0 so you got x/x=1 so limit is 1 |
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by the way you can find a proof in many books, but I don't remember it, it's kinda classic though |
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could you maybe search that site for it because my english is not THAT good and i'll never find that |
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now i didn't expect something like that |
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There's an easier way to prove it, but I don't remember. I studied this 3 years ago. |
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thanks a bunch ecna !! omfg! i never expected something like that... thought that this could be made with just the information i got about limits. you know like the cauchy law or the heine law... |
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Haha it's easier. lim(x->0) [sin(x)/x] = lim(x->0)[(sin(x)-sin(0))/(x-0)] = d(sin(x))/dx (for x=0) = cos(0) = 1 =) |
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well... if you are supposed to know that d(sin(x))/dx = cos(x) dunno, maybe you prove the derivation KNOWING lim(sin(x))/x |
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combo: omg... i think i'll just leave that... that a bit too much for me i guess |
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maybe somehow easier ?? i cannot believe our teacher wants to now something like that from us... |
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use Taylor expansion of (sin x)/x |
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mmmmh maybe too complex lol |
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Combo: Taylor Expansion= Développement limité (si tu connais lol :) ) |
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Sounds like something a problem i had for 3. years ago. But, sorry cant help you, my mathknowlegde is long gone... |
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carry the 1 |
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L`Hopitals rule perhaps... as combo says.. |
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well don't mind that's what you used in your post....I'm too tired lol |
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this is like a fucking nightmare come true. |
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yeah, hospitals rule. they make sick people healthy lol |
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i wonder when it's my turn |
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you're up next, son |
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maths terrifies me, and i am ashamed of this. i have forgotten almost every bit of maths i have ever known, i think maths :( |
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Not being good at math cuts you out of so many interesting jobs. It really sucks. |
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wow, you study maths in english ? impressive ! |
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of course, eveybody knows that ; ) read my first post |
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My friend Ben just asked for help with maths as well. When will mathmaticians do their own work and realise that I am not a genius! |
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i finally got it - the teacher wanted the way with the "d" 's... d(sinx) etc. |
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use definition of limit: delta epsilon thing. that is you want to show that given a real number, m, you can show another one, u. such that if |x| < u then |sinx/x - 1| < m. wich ain't that easy. the easiest way is by definition of derivative like combo suggested. |
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