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On April 08 2011 08:28 MajorityofOne wrote:Show nested quote +On April 08 2011 08:25 Tschis wrote: So funny how majority of people count as 288, then most are studying, and then most see it as 1/(2*x), which is basically the contrary
//tx This is whats confusing me O.O But I think I get it now. The answer is to lose your whole f**king base.
Please look at the number of voters, and realize it was a poll added after the original post, and that the same signs are not used in both polls.
ECAEKAAA is my Chemistry Organic compounds acronym. I'm not a fan of using acronyms to explain ideas. Fine for memorizing though.
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x(y) = (xy)
z/x(y) =/= z/(xy)
z/x(y) = (zy)/x
O.o
Ow, my brain hurts!!!
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On April 08 2011 08:34 VALERO wrote: are people voting the wrong answers as a joke? there's no way that many people could get 5th grade math wrong You are lucky you were taught correctly, all I can say.
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lol what a shittily written and ambiguous expression (as many have noted already)
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On April 08 2011 05:50 44Lunchbox wrote: I guess this thread shows that American's make up most of TL.
:\
User was temp banned for this post.
When being snarky about another country's basic education, it's probably a good idea to know how apostrophes work... :D
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On April 08 2011 08:35 Blisse wrote:Show nested quote +On April 08 2011 08:28 MajorityofOne wrote:On April 08 2011 08:25 Tschis wrote: So funny how majority of people count as 288, then most are studying, and then most see it as 1/(2*x), which is basically the contrary
//tx This is whats confusing me O.O But I think I get it now. The answer is to lose your whole f**king base. Please look at the number of voters, and realize it was a poll added after the original post, and that the same signs are not used in both polls. ECAEKAAA is my Chemistry Organic compounds acronym. I'm not a fan of using acronyms to explain ideas. Fine for memorizing though.
So everybody who voted 2 on the original poll came back to vote 1/(2*x), but the entire 288 crowd is absent? ^^ Either that, or people are voting crazy
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On April 08 2011 08:38 Entropic wrote: lol what a shittily written and ambiguous expression (as many have noted already)
It's 0% ambiguous, but 100% a test of your understanding of math.
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WolframAlpha reads y=1/2x as y=1/(2x)
but it reads y=1/2*x as y=(1/2)x
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Honestly after taking university math for a year and a half I've gotten into the habit of seeing any constant times X as a singular statement so 2(12) to me is automatically 24.
This is definitely a syndrome of too much university mathematics =(.
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On April 08 2011 08:38 Monoxide wrote:This is pretty interesting. Just put in the appropriate parenthesis imo. I answered 2 as well. On a side note... about the 1/2x thing http://www.wolframalpha.com/input/?i=1/2x
This is interesting..
1/2x
Some people see
1x ----- 2
others see
1 ----- 2x
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On April 08 2011 08:18 MandoRelease wrote:Show nested quote +On April 08 2011 08:04 munchmunch wrote:On April 08 2011 08:02 Zeke50100 wrote:On April 08 2011 08:01 munchmunch wrote: [ Not due to laziness at all, actually. Granted, it would be incorrect to omit the parentheses in many contexts, but in any context where it can be expected to be unambiguous to the reader, it would be recommended to any mathematical writer to drop the parentheses for aesthetic reasons.
Being accustomed to the omission of parentheses doesn't make it right No, but aesthetics can be a good reason. Not in anything that does not involves advanced mathematics. I certainly agree that you sometime need to lower your accuracy when you write advanced mathematical paper in order to make it understandable. It is not the case for basic math like trigonometry and basically anything put on a non mathematical forum. For these, it's only lazyness because adding parentheses here and there would not make it any less clear, so aesthetics is not always a good reason.
Ok, I guess I should write a longer post on my thoughts on this subject. Recall that the original subject was about whether something like cos 2x is an incorrect statement for cos(2x). There is no doubt that it is helpful for beginning students to put the brackets in. And every student should understand that there is an unambiguous idea, essentially "perform the multiplication 2 * x and then evaluate the function cos at 2*x", which can be communicated unambiguously by adding the brackets. It would also be nice if people knew that this statement can be made so clear that a computer can understand it, although a computer might require something like "cos(2*x)" or "(cos (* 2 x))".
However, none of that means that cos 2x is wrong! My emotion towards people who perpetuate this sentiment is similar to that contained in Stephen Fry's language rant. As long as the notation is understood, it is never wrong to write cos 2x. And it can sometimes be better to write cos 2x. In differential geometry, for example, if you add parentheses everywhere they might be required, the large amount of parentheses can impede readability.
This is not to contradict you; no doubt cos(2x) is a better choice for a homework thread on TL, for example. But that just means that other considerations are preeminent in that situation.
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I'm studying Physics and can assure you the answer is 288. It IS NOT 2!
1/2x is (1/2)x or 0.5x
Good thing I got the rights answers.
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why does many people say BPEMDAS and got 2.... as clearly shown 2 isnt in the bracket so it is not affected by the bracket, and because multiplication and division is done left to right. its not shittily written... there is no trick in this question as well you just got the basics wrong deal with it and stop whining about the problem being so shtty
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On April 08 2011 08:39 MajorityofOne wrote:Show nested quote +On April 08 2011 08:35 Blisse wrote:On April 08 2011 08:28 MajorityofOne wrote:On April 08 2011 08:25 Tschis wrote: So funny how majority of people count as 288, then most are studying, and then most see it as 1/(2*x), which is basically the contrary
//tx This is whats confusing me O.O But I think I get it now. The answer is to lose your whole f**king base. Please look at the number of voters, and realize it was a poll added after the original post, and that the same signs are not used in both polls. ECAEKAAA is my Chemistry Organic compounds acronym. I'm not a fan of using acronyms to explain ideas. Fine for memorizing though. So everybody who voted 2 on the original poll came back to vote 1/(2*x), but the entire 288 crowd is absent? ^^ Either that, or people are voting crazy
Then you read the second part of my sentence, which says the same signs are not used in both polls. Ugh, read.
1/2x looks different from 1÷2x.
On April 08 2011 08:42 kenwoo wrote: why does many people say BPEMDAS and got 2.... as clearly shown 2 isnt in the bracket so it is not affected by the bracket, and because multiplication and division is done left to right. its not shittily written... there is no trick in this question as well you just got the basics wrong deal with it and stop whining about the problem being so shtty
Grow up.
If you see 2(x+y), you think, 2x+2y. Same applies here. 1/2(x+y), some think, 1/(2x+2y), others think, (1/2)x+(1/2)y.
Internet notation does not work.
And I want to see the rule where they clearly say, go left to right. Also I want to see the rule where we assume 1/2(1+2) is automatically (1)(1/2)(1+2), not 1/[2(1+2)].
Some people see || as OR. Some people see || as PARALLEL.
It depends how you interpret the question.
Arguing there's no ambiguity is senseless.
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what was the answer to the questions then? the polls dont help since maths majors could still be wrong.
i voted 2 for the first question, and the second question isnt even worth voting for.
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Alright guys, it's a very simple solution.
If you're considering machine communication, then any computer or calculator would interpret 1/2x as "x/2." Just put it in your calculator right now. If I pick up my TI-83 and input "1/2*3", it will put the 3 in the numerator. That would be the "correct" answer if it's the context in which we are doing these math problems.
If you're considering human communication, where someone is just trying to convey a question to someone else, then the question asker must be more specific. Seriously, just add a single set of parentheses. He's being unnecessarily ambiguous.
EDIT: Ah, I did not know WolframAlpha did that. Then it that case, even machines will interpret this differently. In any case, I would add parentheses to be safe.
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On April 08 2011 08:25 Tschis wrote: So funny how majority of people count as 288, then most are studying, and then most see it as 1/(2*x), which is basically the contrary
//tx
Not entirely, I assume that's because when you see 1/4(13213213+21312) you will apply the normal rules but for 1/2x you will assume it's (2*x) because it's lazymode.
Edit: I can assume not using brackets when you're lazy and telling something to a friend still wrong and confusing though. Aside from on the computer you will never encounter this problem, and in nearly every math program 1/2x will be seen as (1/2)*x though often they are even annoying and make you explicitely write the *.
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On April 08 2011 08:40 munchmunch wrote:Show nested quote +On April 08 2011 08:18 MandoRelease wrote:On April 08 2011 08:04 munchmunch wrote:On April 08 2011 08:02 Zeke50100 wrote:On April 08 2011 08:01 munchmunch wrote: [ Not due to laziness at all, actually. Granted, it would be incorrect to omit the parentheses in many contexts, but in any context where it can be expected to be unambiguous to the reader, it would be recommended to any mathematical writer to drop the parentheses for aesthetic reasons.
Being accustomed to the omission of parentheses doesn't make it right No, but aesthetics can be a good reason. Not in anything that does not involves advanced mathematics. I certainly agree that you sometime need to lower your accuracy when you write advanced mathematical paper in order to make it understandable. It is not the case for basic math like trigonometry and basically anything put on a non mathematical forum. For these, it's only lazyness because adding parentheses here and there would not make it any less clear, so aesthetics is not always a good reason. Ok, I guess I should write a longer post on my thoughts on this subject. Recall that the original subject was about whether something like cos 2x is an incorrect statement for cos(2x). There is no doubt that it is helpful for beginning students to put the brackets in. And every student should understand that there is an unambiguous idea, essentially "perform the multiplication 2 * x and then evaluate the function cos at 2*x", which can be communicated unambiguously by adding the brackets. It would also be nice if people knew that this statement can be made so clear that a computer can understand it, although a computer might require something like "cos(2*x)" or "(cos (* 2 x))". However, none of that means that cos 2x is wrong! My emotion towards people who perpetuate this sentiment is similar to that contained in Stephen Fry's language rant. As long as the notation is understood, it is never wrong to write cos 2x. And it can sometimes be better to write cos 2x. In differential geometry, for example, if you add parentheses everywhere they might be required, the large amount of parentheses can impede readability. This is not to contradict you; no doubt cos(2x) is a better choice for a homework thread on TL, for example. But that just means that other considerations are preeminent in that situation.
The problem is that cos2x is NOT equal to cos(2x). It IS wrong. It's not comparable to Fry's language rant at all, because there is a right and a wrong when it comes to math and mathematical notation.
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LOL so many weak minded people in this thread
User was warned for this post
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