Poll: dont read the thread, just answer

16
87 51.5%
-16
67 39.6%
I don't know how to do this math
15 8.9%

Status: Voting has ended

168 Total Votes

Poll -4^2 (Read 10413 times)

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1) math's is shitty
2) nobody cares
3) count some red cars faggit
4) ?
5) profit
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dragonx I know at least one person who defends you because you do math well. keep up the good work.
brian chemicals
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Are you kidding me? That is taught in like 3rd grade or something. Everyone knows that exponentiation has higher precedence than multiplication and division, what people mess up with is that the unary negation, which places between multiplication (as well as division), and exponentiation. Yes, that is right, -4 * -4 is (-4) * (-4), not -(4 * -4), they just yield the same result, so people don't need to acknowledge this. :)

clearly not everyone knows it because nearly 50% of the votes are wrong!

also everytime you speak i can't understand anything at all you are saying. i did maths for like 13 years (i was good at it, but never took it onto the really advanced shit) and they never used the terms 'unary negation' or 'exponentiation' ever. your examples are also incredibly confusing and really aren't helping to explain what these concepts are to me at all

edit: okay nevermind, i spent way too long before posting this and there was 983590183908513531 new replies. the list of operations explained it to me (the order at least, not what the fuck they are)
Last Edit: February 20, 2009, 08:54:54 pm by Sarevok
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By the way a scientific calculator will treat it as -(4^2) but a graphing calculator which I used in every class from algebra 1 in eighth grade to calculus senior year will treat it as (-4)^2
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thanks sarevok you know where I'm coming from. i did have to look up those terms but they were concepts i recognised.
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well no, it'd be x = (-4) or x = (-1 * 4)

or x = 4 = (2*2)
But like I already explained in my earlier post, you don't expand -4 to -1*4 to get the correct answer. That's not how it works. Sure, -1*4 = -4, but if you really wanted to expand some expression to some other expression, you're required to add parenthesis around it.
I.e. -4^2 can't be expanded to -1*4^2, for the same reason it can't be expanded to -2*2^2 (which would give different result than -4^2), although both -1*4 and -2*2 result in -4. If you wanted to expand it, -4^2 would be (-1*4)^2, which wouldn't help solving the issue at hand *at all*

big thanx to dragonslayer for sig!
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By the way a scientific calculator will treat it as -(4^2) but a graphing calculator which I used in every class from algebra 1 in eighth grade to calculus senior year will treat it as (-4)^2
what kind of graphing calculator are YOU using??? If you input -4^2, it will output -16
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But like I already explained in my earlier post, you don't expand -4 to -1*4 to get the correct answer. That's not how it works. Sure, -1*4 = -4, but if you really wanted to expand some expression to some other expression, you're required to add parenthesis around it.
I.e. -4^2 can't be expanded to -1*4^2, for the same reason it can't be expanded to -2*2^2 (which would give different result than -4^2), although both -1*4 and -2*2 result in -4. If you wanted to expand it, -4^2 would be (-1*4)^2, which wouldn't help solving the issue at hand *at all*

well I know I was just explaining to steel that you cant just say x = 4 so x = 2*2 it has to be (2*2) the whole -4^2 thing is just bad form imo
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clearly not everyone knows it because nearly 50% of the votes are wrong!

also everytime you speak i can't understand anything at all you are saying. i did maths for like 13 years (i was good at it, but never took it onto the really advanced shit) and they never used the terms 'unary negation' or 'exponentiation' ever. your examples are also incredibly confusing and really aren't helping to explain what these concepts are to me at all
Well sorry! Also you're wrong, everyone (well 95% of people anyway) knows how exponentiation works. Everyone knows that 2*5^2 is 2*(5^2) and not (2*5)^2. That's what I meant when I said that surely Rockman has been taught this. This is *very* basic maths. What people get confused in -4^2 is the fact that they don't know about the fact that negation of a real number is an operation of its own, and it has lower order of operation than exponentiation.

big thanx to dragonslayer for sig!
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clearly not everyone knows it because nearly 50% of the votes are wrong!

what? who doesn't know PEMDAS? I learned that in middle school. he's right what people are messing up is squaring the negative, not the exponent itself.
brian chemicals
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Try to describe a beautiful swan with 'numbers' asshole mathematicians

you can't because god did it
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Quote
they don't know about the fact that negation of a real number is an operation of its own, and it has lower order of operation than exponentiation.

this is it btw. I wonder why this isn't in the PEMDAS thing but yeah rami's right ignore my previous post about -1*4 which is really an incorrect way of explaining it.
brian chemicals
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hey guess what I haven't been taught in those terms and neither has Sarevok is there a pattern here?
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                           ...,ooooooooo......
                      .o8888888888888888888888888o.
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           88888888888V                  V88888v  "88888888888
           88888888888v                            "8888888888
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:::::::::::::::::::::          :::.   ::::::::::::::::::::::::::::::::::::
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here you go mark
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I've never heard of pedmas, just bodmas. pedmas seems better
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Wtf is PEDMAS, it's BEDMAS!!
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this is it btw. I wonder why this isn't in the PEMDAS thing but yeah rami's right ignore my previous post about -1*4 which is really an incorrect way of explaining it.

tbh thats not a horrible way of explaining it, since negation is basically just multiplying by -1 and multiplication has a lower order of operation!!!!

so -1 * (4) is fine....o_o;
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hey guess what I haven't been taught in those terms and neither has Sarevok is there a pattern here?

there isn't really, thats why I made this topic; I originally assumed it might be the US only but if both of you guys made the mistake this means its just something that isn't covered.

Wtf is PEDMAS, it's BEDMAS!!
I've never heard of pedmas, just bodmas. pedmas seems better

isn't it still BEMDAS, or is it BEDMAS/BODMAS more common?
brian chemicals
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btw i kind of can agree with those who say I CANT UNDERSTAND WHAT RAMIREZ IS SAYING!!! because he does tend to use the technical phrasing for everything instead of layman's terms. He is very logical about his explanations which, I'm pretty sure is because of his line of work.



Basically, for those of you who don't understand why the answer is "-16": You just need to understand order of operations.

The exponent sign (^) only refers to the 4. It does not refer to the "-4". If you wanted the exponent to square the entire term, you would have to include parentheses. Since there are no parentheses, the order of operations instructs you to do as follows:

4^2 = 16
-(16) = -16

Exponents first, multiplication (which is what "-" refers to) second.
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order of operations is so gay does it actually have any purpose beyond teachers making really weird math problems to fuck with us

IS IT A DECIMAL POINT OR A SPECK OF DUST CAUGHT ON THE SCANNER I'LL NEVER TELL

we should just do parentheses wherever it's confusing like in C++ etc. can't you do this in math already if you're a decent human being and don't want to confuse people
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