12:16 AM <laurus> joel135, my problem is, I don't see how a "proof by contradiction" is a proof of anything.
12:16 AM <opraaaa> I need to find out what values of x have a slope of 0
12:16 AM <Svitkona> values don't have slopes
12:16 AM <opraaaa> So when I plug in x, it will give me 0
12:16 AM <Svitkona> that's what i'm saying
12:17 AM <laurus> joel135, for example, in the third line, we get 0. So what? That tells us that q is 0.
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12:17 AM <minn> laurus: That isn't abnormal, because proofs by contradiction aren't constructive. You must trust the truth table until you've trained yourself to think in terms of classical logic!
12:17 AM <Svitkona> you can think of the derivative as the value of the slope at some point
12:17 AM <opraaaa> Svitkona, let me screenshot the question
12:17 AM <laurus> minn, what do you mean exactly?
12:17 AM <Svitkona> so you are trying to see when the derivative (ie. the slope) is 0
12:17 AM <Svitkona> which is exactly what i said
12:17 AM <opraaa__> https://usercontent.irccloud-cdn.com/file/LqYvRcYm/1462486660.JPG

1462486660.JPG164.04KB • image/jpeg
12:17 AM <opraaaa> #9
12:17 AM <laurus> minn, I understand how the two statements are logically equivalent.
12:17 AM <laurus> minn, but I don't see how that tells you anything, or helps at all.
12:18 AM <laurus> It just seems pointless.
12:18 AM <Svitkona> that still doesn't change what i'm saying
12:18 AM <opraaaa> Svitkona, okay so the first thing I do is get the derivative
12:18 AM <opraaaa> Then simplify
12:18 AM <opraaaa> I have now simplified
12:18 AM <opraaaa> Now what
12:18 AM <laurus> And when I try to focus in on the rows where the premises are true in order to "establish the validity of the argument" I get nowhere.
12:18 AM <Svitkona> you need to find the values of x that will make the derivative 0
12:18 AM <opraaaa> Right how do I do that
12:18 AM <Svitkona> you set it to 0 and solve
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12:19 AM <opraaaa> Right so I set it to 0
12:19 AM <opraaaa> Now what
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12:19 AM <Svitkona> did you read what i said above about fractions?
12:19 AM <opraaaa> 0 = (2x(x-8))/(x-4)^2
12:19 AM <opraaaa> I don't understand it
12:19 AM <Svitkona> ok let me say it again
12:19 AM <joel135> laurus: One problem in practice is that proofs by contradiction are weak unless you know how to tell whether the things you are talking about are true or false. This kind of logic operates on values 0 and 1. To use it in practice (outside this word of logic) you need a way to convert your statements to 0 and 1. Proofs by contradiction do not provide a method
12:19 AM <joel135> for performing such conversions.
12:19 AM <Svitkona> and tell me which part of it you are having trouble with
12:19 AM <Polymorphism> I passed math!
12:19 AM <opraaaa> Alright
12:19 AM <Svitkona> if you have a fraction, the whole fraction will be 0 if: the numerator is 0 (and the denominator is not 0 at the same time)
12:19 AM <Polymorphism> can someone please link me the best explanation of the calculus for a beginner
12:20 AM <opraaaa> Svitkona, right
12:20 AM <minn> laurus: In classical logic, p v ~p holds for every proposition p. If p is false, then p holds by disjunctive syllogism. If p is true, then --p <-> p holds by disjunctive syllogism.
12:20 AM <opraaaa> Which is why we do things like rationalizing and stuff
12:20 AM <laurus> minn, right.
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12:20 AM <Svitkona> i don't see what rationalising has to do with it but whatever
12:20 AM <opraaaa> Sorry was just making a connection
12:20 AM <minn> laurus: The truth table is just a proof procedure that verifies that informal argument.
12:20 AM <Svitkona> opraaaa, so what's the numerator in your fraction?
12:20 AM <opraaaa> 2x(x-8)
12:20 AM <Svitkona> and what's the denominator?
12:21 AM <opraaaa> (x-4)^2
12:21 AM <Svitkona> can you solve 2x(x - 8) = 0?
12:21 AM <opraaaa> err
12:21 AM <opraaaa> x=0,8
12:21 AM <Svitkona> how did you get those answers?
12:21 AM <opraaaa> I divided 0 by 2x
12:21 AM <opraaaa> Then added 8
12:21 AM <opraaaa> OR
12:22 AM <laurus> joel135, well I do see that
12:22 AM <opraaaa> I divided 0 by x-8
12:22 AM <opraaaa> And then divided it by 2
12:22 AM <laurus> joel135, I still don't get how to use it even when we *do* know the values.

[...]

12:30 AM <laurus> joel135, minn: Forget about "establish the validity of the argument;" that method doesn't work here.
12:31 AM <laurus> Instead, look at rows 1, 2, and 4, i.e. when the statement is true.
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12:31 AM <laurus> Notice that the only time a statement with a false conclusion is true is when one or more of the premises is false.
12:31 AM <laurus> Now if we assume that p is absolutely true (since we chose it correctly), the only possibility is that "not q" is false. Therefore q is true.
12:32 AM <eliasf> opraaaa, what is it that you dont understand?
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12:32 AM <joel135> Sounds good.
12:32 AM <opraaaa> How do I solve for x
12:32 AM <laurus> joel135, minn: But, there's a big caveat to this. It only works if you are 100% sure you have landed on rows 1, 2, or 4 in the first place.
12:32 AM <monoprotic> opraaaa your last linei s factored wrong
12:32 AM <laurus> So it doesn't work like the normal "establish the validity of the argument" stuff.
12:33 AM <opraaaa> monoprotic, yeah I noticed that
12:33 AM <opraaaa> I fixed it now
12:33 AM <opraaaa> But what do I do next
12:33 AM <laurus> Therefore I conclude that this is a weak and error-prone way of doing things.
12:33 AM <monoprotic> opraaaa other than that, you're almost there. you can ignore the denominator when solving for 0
12:33 AM <monoprotic> opraaaa so solve 2x(x-8) = 0
12:33 AM <opraaaa> Just multiply it out right?
12:33 AM <Svitkona> only when the denominator is not 0.
12:33 AM <monoprotic> yes yes
12:33 AM <opraaaa> GOD SVIT PLS
12:33 AM <opraaaa> PLS
12:33 AM <monoprotic> s/hes right
12:33 AM <opraaaa> I DONT GET IT
12:33 AM <eliasf> 0/0 is undefined
12:33 AM <opraaaa> Of course!
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12:33 AM <opraaaa> Then it's an unsolvable equation
12:33 AM <opraaaa> And x=0 doesn't exist
12:34 AM <laurus> It only works when you are 100% sure of every single premise except that one premise, *and* when you are 100% sure you have arrived at "false."
12:34 AM <joel135> laurus: Would you like to hear my way of doing things?
12:34 AM <eliasf> so you have to check that the denominator is not 0
12:34 AM <laurus> joel135, yes, please! :)
12:34 AM <eliasf> to make sure that its defined
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12:34 AM <monoprotic> opraaaa but here there is no x such that you get 0/0
12:34 AM <opraaaa> How would I do that
12:34 AM <joel135> Forget all you know.
12:34 AM <opraaaa> How could I make sure it doesn't equal 0
12:34 AM <eliasf> just substitute x
12:34 AM <eliasf> with a value
12:34 AM <eliasf> and check that its not 0
12:34 AM <joel135> Including the words "or", "contradiction", "induction", "equals".
12:34 AM <opraaaa> Any value?
12:35 AM <opraaaa> Like x=4 would make it 0
12:35 AM <eliasf> yes
12:35 AM <opraaaa> So there is an asimptote at 4?
12:35 AM <joel135> There is one fundamental way of representing statements: by stringing them together in a list. Stating a list is stating that everything in the list is true.
12:36 AM <opraaaa> Is that right?
12:36 AM <laurus> joel135, okay.
12:36 AM <eliasf> i dont know
12:36 AM <joel135> By the way, the word "not" must also be forgotten.
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12:36 AM <laurus> Ok.
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12:37 AM <eliasf> you just find the values for which 2x(x-8) is 0, and make sure that the denominator is not 0 for those values
12:37 AM <joel135> The next most important thing is the implication. To say a => b means that if we fantasize about a then we will discover b.
12:38 AM <laurus> joel135, okay.
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12:39 AM <joel135> At this stage, let's consider an example. There are no axioms. We want to prove that always (a => b), (b => c) => (a => c).
12:39 AM <eliasf> does that make sense opraaaa ?
12:39 AM <laurus> joel135, okay.
12:39 AM <opraaaa> Yeah :)
12:39 AM <opraaaa> Thanks!
12:39 AM <eliasf> no problem
12:39 AM <joel135> Do this by fantasizing about (a => b), (b => c), aiming to prove c.
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12:39 AM <joel135> Sorry
12:39 AM <laurus> Okay
12:39 AM <joel135> aiming to prove (a => c).
12:40 AM <minn> joel135: But a => a for all propositions a, and I don't get everything I want :D
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12:40 AM <joel135> minn: What do you mean?
12:40 AM <eliasf> a -> a is valid
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12:41 AM <minn> You said "[to] say a => b means that if we fantasize about a then we will discover b." It was a dumb joke, I apologize.
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12:41 AM <laurus> joel135, with you so far
12:41 AM <joel135> ok
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12:43 AM <joel135> So in this fantasy (a => b), (b => c) we want to prove (a => c). Do this by fantasizing about a.
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12:44 AM <joel135> Here's a rule of simplification, which will be generalized later: if a is true and a => b then a => b *means* b.
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12:44 AM <joel135> Sorry
12:44 AM <laurus> joel135, okay
12:44 AM <joel135> if a is true then a => b *means* b.
12:45 AM <laurus> Ok
12:45 AM <joel135> a. (a => b) i.e. b. (b => c) i.e. c.
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12:46 AM <laurus> Ok
12:46 AM <joel135> So c is true. Thus (a => c) in the fantasy (a => b), (b => c). Thus (a => b), (b => c) => (a => c).
12:46 AM <laurus> Alright
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12:46 AM <nollyyy> I'm programming a simulation requiring trig and 0 degrees is upward and not to the the right like regular math. :/
12:46 AM <joel135> Now let me introduce the word "not". I will be as careful as I can.
12:46 AM <laurus> joel135, ok
12:46 AM <Polymorphism> the discrete pocket catheter, curved to fit in your pocket to go *anywhere*
12:46 AM <Polymorphism> sorry wrong window
12:47 AM <joel135> The key idea is that we must define what we mean by "not".
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12:48 AM <laurus> joel135, I think you'd better stop here actually :)
12:48 AM <laurus> I'm afraid I'm going to get re-confused again
12:49 AM <eliasf> dont be a pessimist
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12:49 AM <joel135> No, come on. It is good to consider new things. I'll continue.
12:49 AM <laurus> joel135, all right.
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12:51 AM <joel135> When choosing meanings for "not" we need a criterion to guide us. This criterion is: If a, not a then we can prove anything.
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12:52 AM <joel135> I choose to define not (a, b) as follows: a => not b.
12:52 AM <laurus> All right
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12:53 AM <joel135> Is this reasonable? Well, fantasize about (a, b), a => not b.
12:53 AM <joel135> Then b, not b.
12:54 AM Vogone → Vgn|away
12:54 AM <joel135> If we have defined "not" according to the above criterion in all other places, then we can prove anything in this fantasy. Thus our definition is okay, according to the criterion.
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12:55 AM <joel135> Maybe more precisely, if we have defined "not" according to the above criterion for b, then we can prove anything in this fantasy. Thus our definition is okay, according to the criterion.
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12:55 AM <laurus> Alright.
12:55 AM <joel135> There is a small problem about infinite recursion here. Shall we let that slide for now?
12:56 AM <laurus> Yes
12:56 AM <laurus> :P
12:56 AM <joel135> ok :)
12:56 AM <joel135> Note that at this point, we do not know that "not not a" always *means* a. We will get to that soon.
12:57 AM <joel135> But first, let's define not (a => b).
12:57 AM <laurus> Ok
12:57 AM <joel135> It shall mean a, not b.
12:58 AM ↔ josefig nipped out
12:58 AM <joel135> We now notice something: not not (a, b) means not (a => not b), which in turn means (a, not not b).
12:59 AM <laurus> Hm, right.
12:59 AM <joel135> (By the way that definition meets the criterion. Exercise.)
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12:59 AM <joel135> Someone show me that the definition of not (a => b) meets the criterion.
12:59 AM <laurus> Ok
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1:00 AM <laurus> joel135, I'm listening to the continuation of your explanation
1:00 AM <joel135> Don't you want to complete the exercise first?
1:00 AM <math675> So if you solved an equation that solves the issue of fermat in one page or less in a proof who would you contact.
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1:00 AM <laurus> joel135, my brain is kind of exhausted from thinking about this issue for these past few hours
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1:01 AM <eliasf> math675, anyone who can tell you that you havent
1:01 AM <nollyyy> trying to move an object along angle "a". it's not going correctly: http://pastebin.com/FkfxAHZU

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1:01 AM <eliasf> math675, just email someone at your closes university
1:02 AM <joel135> Does anyone else want to try the exercise? Otherwise I will continue.
1:02 AM <math675> ha my own department is snoozing. nobody believes you nobody believed einstein. but I do have it.
1:02 AM <eliasf> one page dude
1:02 AM <eliasf> its not a matter of belief
1:02 AM <math675> yes
1:02 AM <Svitkona> nollyyy, what's the point of condition in the if statement?
1:02 AM <math675> yes
1:02 AM <math675> I know
1:02 AM <eliasf> just get someone to check it
1:03 AM <math675> already did
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1:03 AM <eliasf> well congratulations on the fields medal then
1:03 AM <nollyyy> Svitkona: to try to get it to move correctly on the y axis when less than 180.
1:03 AM <math675> in confidence with a professor of mathematics.
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1:03 AM <QwertyDL> What is the difference beteeen data/datum and a mathematical obkect in general?
1:03 AM <nollyyy> i think it might be helping a bit. been experimenting
1:03 AM <Svitkona> did you try without any if statements?
1:03 AM <eliasf> and this person didnt know who to contact? come on
1:04 AM <kadoban> math675: And what'd they say?
1:04 AM <math675> she respects my right
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1:04 AM <QwertyDL> All datum are mathematical fundamrntally? If not, then what. In othet words
1:04 AM <math675> and she agrees most of the education system is tarnished here
1:04 AM <joel135> I'll continue. We noticed that not not (a, b) means (a, not not b). For now, I will use the symbol "=" to denote "means". Furthermore, notice that not not (a => b) = not (a, not b) = (a => not not b).
1:05 AM <kadoban> math675: She looked over your mathematical proof and said "I respect your right"? That … doesn't seem to make any sense.
1:05 AM <math675> I have multiple axioms
1:05 AM <nollyyy> Svitkona: yes. Ihave to do Math.blah(angle + changeInAngleApplied) though for some reason to work. even then you can see the x and y axis both moving it a bit odly
1:05 AM <QwertyDL> I indetstand now
1:05 AM <nollyyy> like when it
1:05 AM <Svitkona> what is changeInAngleApplied?
1:05 AM <QwertyDL> Hanks
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1:06 AM <math675> and my final solution hinges on equality by being n=0 so yes.
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1:06 AM <math675> and if is not the system stops and resets
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1:06 AM <nollyyy> I press A key to change angle by +45. adding it to it seems to make it work almost perfectly
1:06 AM <joel135> Let's now agree, after having defined "not" in two cases, that not not a should always be just a.
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1:07 AM <eliasf> math675, just show us your paper
1:07 AM <laurus> joel135, ok
1:07 AM <kadoban> math675: No, I mean the response you're saying she gave literally makes no sense. If I gave a proof of something to someone and their response was "I respect your right", I would ask them to rephrase it, because that literally makes no sense.
1:07 AM <Svitkona> nollyyy, so when you press A, it doesn't directly add to the angle ?
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1:08 AM <joel135> But look! not (a, not b) = (a => not not b) = (a => b).
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1:08 AM <laurus> joel135, :)
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1:10 AM <nollyyy> Svitkona: pressing a does add to it. I realize I'm being unclear, here: http://pastebin.com/yzf4EFHM

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1:10 AM <eliasf> math675, just share your proof
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1:11 AM <Svitkona> looks like you add 45 twice: once under if(Pressed(Keys.A)) and then another time after the if block
1:11 AM <joel135> This is means the word "implies" and the symbol "=>" are redundant. Although they have important meaning, the words themselves are now unnecessary. Keep that in mind. Everything boils down to lists "(a, b, c, ..., z)" and negations "not a".
1:11 AM <Svitkona> is that intended?
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1:11 AM <laurus> OK joel135
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1:12 AM <joel135> I will use "-" to denote "not". I will now define the word "or".
1:12 AM <nollyyy> adding 45 under a key press is but when doing Math.cos(a) adding 45 seems to make it work. without it, it behaves a little odd.
1:12 AM <joel135> a or b means that given any c such that (a => c) and (b => c), we deduce c.
1:13 AM <nollyyy> Svitkona: I assume because 0 degrees is upwards
1:13 AM <Svitkona> does Math.cos(a) take input in degrees or radians?
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1:13 AM <math675> thank you and it's one inch long and explains and unifies physics and the issue of gravity in a single theory.
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1:13 AM <math675> =)
1:13 AM <eliasf> hahaha
1:13 AM <eliasf> lets see it then
1:13 AM <nollyyy> Svitkona: reading the specifications it says radians. uh oh
1:13 AM <joel135> In symbols, a or b = -(-(a, -c), -(b, -c), -c). Take some time to think about that.
1:13 AM <Svitkona> hm ok
1:14 AM <Svitkona> is there another function for degrees?
1:14 AM <laurus> joel135, ok
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1:14 AM <nollyyy> I think  Math.cos(Math.ToDegrees(a)) would make it degrees
1:14 AM <math675>  X=z  aX+bX=CX or aX+c   CX/d=e   e/X=f   f≥X   X=y  Anti Solution X>z=a  if a=0 a=a continue
1:15 AM <Svitkona> try Math.cos(Math.ToRadians(a)) instead
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1:15 AM <Svitkona> assuming everything on your side is in degrees, and the function works in radians, that should work
1:15 AM <eliasf> math675, that makes no sense
1:16 AM <joel135> I love this way of writing things. -(-(a, -c), -(b, -c), -c). It is very uniform. You can read the symbol combination "-(" as "if". Later you then must read "-a)" as "then a".
1:16 AM <math675> I know because it basis is new identity of mathematics unification
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1:16 AM <joel135> So "if if a then c and if b then c then c".
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1:16 AM <joel135> Every word I just said corresponds to a symbol.
1:17 AM <nollyyy> Svitkona: it works! Only thing is the rendering shows it 45 degrees off but i can fix that.
1:17 AM <Svitkona> alright
1:17 AM <nollyyy> I'll start reading more on understanding radians
1:17 AM <nollyyy> thank you though
1:17 AM <Svitkona> they're just another unit of measurement for angles
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1:18 AM <math675> so if x>z = dead
1:18 AM <Svitkona> they're a lot more "natural" than degrees
1:18 AM <laurus> joel135, it is helpful
1:18 AM <Svitkona> but yeah
1:18 AM <joel135> :D
1:18 AM <laurus> Thank you for explaining this
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1:18 AM <eliasf> dead?
1:18 AM <nollyyy> they're just the number i get when I do opposite/hypothenuse etc?
1:18 AM <math675> yup\
1:18 AM <Svitkona> er not really
1:18 AM <laurus> I apreciate it!
1:18 AM <math675> breakdown of physical universe
1:18 AM <Svitkona> it's defined like this: a full turn is equal to 2pi radians
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1:19 AM <joel135> Next definition: A boolean statement x is such that x or not x.
1:19 AM <Svitkona> in degrees, one full turn is equal to 360 degrees
1:19 AM <laurus> joel135, I am going to have to leave soon unfortunately
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1:19 AM <joel135> laurus: Ok, maybe we have covered enough.
1:20 AM <laurus> joel135, I thank you again
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1:20 AM <nollyyy> got it. also degrees are just a way of visualizing radians right?
1:20 AM <Svitkona> well it's really a bit like feet and metres
1:20 AM <Svitkona> they're both units for measuring distance
1:20 AM <Svitkona> and there are conversion factors between both of them
1:20 AM <Svitkona> and so on
1:20 AM <joel135> No problem :) Thank you for listening!
1:22 AM <laurus> Thanks for taking the time :) I wrote it down so I can refer to it later
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1:24 AM <baxx>  I'm not sure how to do problem 31 here https://www.docdroid.net/QJzhnPU/chrome-extension-mhjfbmdgcfjbbpaeojofohoefgiehjai-index-material.pdf.html
1:25 AM <baxx>  How I've tried it is - using the combinations that are given before it and then drawing out a table (see here http://vpaste.net/CP7Fa ). So that I can have the following for pairs of values, and triples of values. So when  sum up i have 22 ways... I'm not sure if this is right though, or if the reasoning is any use? It doesn't feel very general.
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1:26 AM <Kol> you might need to approach this recursively and come up with a recurrence relation to solve?
1:26 AM <Kol> ie find an operator, put parentheses around the two operands, repeat
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1:26 AM <baxx> Kol: I'm not sure i follow :/
1:27 AM <baxx> oh right, i think i might do. hrm
1:27 AM <Kol> your idea of finding doubles and triplets doesn't scale
1:27 AM <Kol> i think
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1:27 AM <baxx> Kol: probably not, but is it sound for this case?
1:28 AM <Kol> unfortunately i don't have the confidence to have a say :p
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1:28 AM <baxx> Kol: np, how would you actually do it then?
1:28 AM <Kol> well i'd probably build off my idea
1:28 AM <Kol> of choosing operations to group
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1:28 AM <Kol> systematically going through all of the choices
1:28 AM <baxx> well it's just multiplication
1:29 AM <Kol> sure, in this case the exercise might seem pointless
1:29 AM <Kol> but if you change any of those operators to things with higher/lower precedence, then the groupings are quite important
1:30 AM <baxx> yea but this problem is specified to multiplication
1:30 AM <minn> bazz: How many ways can you put parentheses around the individual factors. How many ways can you put parentheses around contiguous groups of two factors? Three factors? And so forth. Then apply the multiplication rule. I think this approach is correct.
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1:30 AM <baxx> minn: i haven't put parens around the individual factors as they weren't used in the previous example like that
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1:31 AM <baxx> minn: here if you didn't see : https://www.docdroid.net/QJzhnPU/chrome-extension-mhjfbmdgcfjbbpaeojofohoefgiehjai-index-material.pdf.html (i'm doing 31)
1:31 AM <minn> I assumed the example wasn't exhaustive, sorry.
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1:32 AM <baxx> minn: no worries, i really don't know what's best tbh. It seems to imply it's enough, maybe i'm being lazy tho idk
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1:33 AM <minn> You can enumerate them by starting with (2 * 3 * 4 * 5) * 6 and 2 * (3 * 4 * 5 * 6), then considering 2 * 3 * 4 * 5 and 3 * 4 * 5 * 6, right?
1:34 AM <minn> I gues there is also (2 * 3) * (3 * 4 * 5) and so forth. But that is systematic.
1:34 AM <minn> So figure that out and then write a recurrence.
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1:35 AM <Kol> baxx http://pastebin.com/BmHsV998 this is what i had in mind

1:35 AM <baxx> i'm not sure what to figure - what do you mean i can enumerate them like that? I've written them out like that
1:35 AM <Kol> i think mine's a bottom-up approach whereas you guys are working on a top-down
1:35 AM <Kol> dunno which is more feasible/correct
1:36 AM <baxx> i have no idea, i'm only on page 13, ace.
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1:42 AM <dhex> hello all. How to do for this integral? http://i.imgur.com/yjhOBEJ.png
1:43 AM <baxx> this is a wrong approach http://vpaste.net/VuZkK
1:43 AM <dhex> baxx, ?
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1:43 AM <baxx> dhex: not related to your problem
1:43 AM <dhex> k
1:43 AM <Svitkona> try integration by parts
1:43 AM <dhex> Anyone can help me please?
1:44 AM <baxx> dhex: svit just did
1:44 AM <dhex> he didn't
1:44 AM <baxx> k
1:44 AM <Svitkona> do you know what integration by parts is?
1:44 AM <dhex> baxx, something wrong?
1:44 AM <baxx> ?
1:44 AM <dhex> Svitkona, I don't know what it is.
1:45 AM <Svitkona> so why are you trying this integral?
1:45 AM <Svitkona> what techniques do you know?
1:45 AM <dhex> because i have exercise
1:45 AM <minn> baxx: If (*) is a binary operation, then the number of ways to parenthesize a1 * ... * an will be the sum of the number of ways to parenthesize each way of decomposing a1 * ... * an into two groups, e.g.: a1 * (a2 * ... * an), (a1 * a2) * (a3 * ... * an), and so forth. This should be a simple enough recurrence to write, but it's surprisingly difficult to solve.
1:45 AM <dhex> idk
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1:45 AM <dhex> x/2 so 0.5x ... 1/x^2 is x^-2
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1:45 AM <dhex> integral is only on the x
1:45 AM <baxx> dhex: get wolfram app on your phone and view the steps, or symbolab / cymath might be useful
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1:46 AM <Svitkona> yes but this isn't in the form x^a
1:46 AM <dhex> baxx, wolfram cost money
1:46 AM <Svitkona> this is log_2(x)
1:46 AM <dhex> this is not helping
1:46 AM <baxx> dhex: yeah like £2
1:46 AM <dhex> baxx, you are not helping
1:46 AM <baxx> dhex: symbo and cymath are free
1:46 AM <Svitkona> are you supposed to use integration tables, dhex ?
1:46 AM <baxx> dhex: get over yourself
1:47 AM <dhex> Svitkona, no
1:47 AM <Svitkona> integration by parts is your best option for this integral
1:47 AM <Svitkona> i don't even know if it can be done in any other way.
1:47 AM <dhex> :(
1:47 AM <Svitkona> if you want an exact result, that is
1:47 AM <dhex> I know integral of x is x^2/2
1:48 AM <minn> baxx: If T(n) denotes the number of ways to parenthesize a1 * ... * an, assuming (*) is a binary operation, it follows that T(b) = sum[i = 1 ... n -1] T(i) * T(n - i).
1:48 AM <dhex> idk about integrals on ln, and logs
1:48 AM <dhex> I know integrals of e^x
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1:49 AM <baxx> minn: thanks, just trying to work out the words there
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1:49 AM <dhex> http://www.cymath.com/answer.php?q=integrate%20log2x
1:49 AM <dhex> omg baxx is trouble maker
1:49 AM <dhex> http://www.cymath.com/answer.php?q=integrate%207%2F3*log2x
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1:51 AM <baxx> dhex: why bother posting that? i don't care if it worked, it's just a suggestion for future reference and such. Try symbolab and stop being a tool
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1:51 AM <dhex> Anyone can help me please?
1:51 AM <dhex> There is 900 people here
1:51 AM <Svitkona> i already told you how to solve your problem
1:51 AM <Svitkona> use integration by parts
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1:52 AM <Svitkona> if all you're looking for is an approximation then use the trapezium rule or some other approximation method for integrals
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1:52 AM <dhex> wtf what rule man
1:52 AM <dhex> stop kill me
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1:53 AM <Kol> lmao
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1:53 AM <Kol> "help me. but i won't undrestand anything you tell me"
1:53 AM <dhex> i am watching a video and it makes me harder
1:53 AM <baxx> Kol: they're on my ignore list now lol
1:53 AM <dhex> Kol, I do understand
1:53 AM <dhex> https://www.youtube.com/watch?v=dqaDSlYdRcs
1:53 AM <dhex> doesn't he suppose to write dx ?
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