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You are currently reading a thread in /sci/ - Science & Math

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Help?
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1
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>>7807552

Brackets first. Then division followed by multiplication. You will get 1. If you didn't you're a low IQ pleb.
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9
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>>7807561
>Brackets first
2(1+2) is implied multiplication, why are you assigning special priority to it?
6/2(1+2)
6/2(3)
6/2*3
3*3 = 9
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>>7807573
multiplication is generally held to come before division

In any event, this is the reason that every math book has a discussion of what specific order of operations conventions that they follow.
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>>7807573
6/2(1+2)
6/(2*1+2*2)
6/(2+4)
6/(6)
6/6
1
>>
Brackets
Exponentials
Division
Multiplication
Subtraction

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>>7807581
>bemdas
>not pemdas
>shiggy
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>>7807580
You're not operating from left to right. Again, why are you assigning special priority to operations OUTSIDE brackets?
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>>7807581
That nigga said beDmas not beMdas.
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>>7807580

This one gets it.
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>>7807587
But Im not? Okay lets try that again
6/2(1+2)
6/2(3)
6/2*3
6/6
1
>>
Depending on the order of operations it's either 1 or 9.

I would say 9, but both can be correct.
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>>7807587
You need to get rid of the parenthesis. Usually you do that by multyiplying everything within by the number outside
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>>7807594
>6/2*3
>6/6
It's left to right. Multiplication and division are on the same tier
6/2*3 = 6*(1/2)*3 = 9
>>7807598
>You need to get rid of the parenthesis
The number outside was 3, not 2
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Press F12, paste this in console:

6 / 2 * (1 + 2)

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I don't understand
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Implied multiplication, the answer *literally* depends on where you live (i.e., the education system)

That being said, the answer is 1 in South Korea.
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>>7807610
>not putting it in a RPN calculator
But seriously, look up in your calculator's instruction book the bit about order of operations, it'll explain the logic used.
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>>7807612
>Implied multiplication, the answer *literally* depends on where you live (i.e., the education system)
No, it *LITERALLY* depends on the conventions used by whoever put it out into the world.
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>>7807606
But you cant divide 6 by 2, thus getting 3, since 2 is 'connected' to the parenthesis.
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>>7807620
That "connection" is implied multiplication, which is on the same tier as division. It's an ambiguous expression though
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>>7807627
7.6255975e+12
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However, in some of the academic literature, implied multiplication is interpreted as having higher precedence than division, so that 1/2x equals 1/(2x), not (1/2)x. For example, the manuscript submission instructions for the Physical Review journals state that multiplication is of higher precedence than division with a slash,[9] and this is also the convention observed in prominent physics textbooks such as the Course of Theoretical Physics by Landau and Lifshitz and the Feynman Lectures on Physics.
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>>7807552
?
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>>7807641
I wouldn't consider a physics textbook an authority when it comes to mathematics, at least not in this case. I think that expamle is a bit cherrypicked, because nobody would write (1/2)x instead of x/2, but we can agree that nobody that's not trolling would write such an ambiguous expression
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>>7807641
>Feynman says 1
9 fags confirmed as brainlets :^)
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6/2(3)
3(3)
9
there faggots
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>>7807651
>>7807651
GOOD GOD. There is no such thing as an authority on order of operations. There literally is no unified, world-recognized order of operations. This is why publications specify in their submission style guides what their specific conventions are, why every math book discusses what order of operation conventions they use, etc.
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>>7807552

By semantix of mathematics, it is equivalent to

(6/2)*(1+2) = 9

Whoever answered one is a fucktard.

These people, congrats.
>>7807568
>>7807573
>>7807662

Whoever answered 1, go kill yourself.
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>>7807580
It could just as easily be done this way too,

6/2(1+2)
6/2 + 12/2
3 + 6
9

But the question is far to ambiguous. The use of the ÷ sign should be left behind once you start dealing with fractions, so about after grade 3 or 4. The question should then be written as,

$\frac{6}{2(1+2)}$

or

$\left\frac{6}{2}\right(1+2)$
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>>7809127
>$\left\frac{6}{2}\right(1+2)$
darn

$\left\frac{6}{2}\right$
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>>7809137
$(\frac{6}{2})(1+2)$
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Doing this: 6÷2(1+2) is retarded anyways. Lisp ordered notation (binary trees) master race:

(*(/ 6 2) (+ 1 2))
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In my secret society of mathematicians, I was told that the division symbol is strictly forbidden due to ambiguity.
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>>7807552
BE(DM)(MS)
All you have to do for the brackets is what's inside them. Thus you get 6/2 * 3. Division and multiplication have equal priority, so once brackets and exponents have been taken care of you simply work out each of them in chronological order. Hence you do 6/2 first, then multiply by 3, giving 9. People get tripped up because normally there isn't a multiplication or division sign in front of a coefficient and its brackets. In those cases you just do the brackets and then multiply it by the coefficient. That's one reason why in professional maths "÷" is almost always replaced by a fraction sign, because when it's shown as a fraction you automatically see that the coeffient is 6/2, not 2.
>>7807561
Nice try, faggot.
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>>7807579
Not true, it's a misconception that comes from PEMDAS. People see D come after M in the mnenomic and so think that it means multiplication comes before division, when in actual fact they have equal priority (just as addition and subtraction have equal priority) since they are merely the opposites of each other.
To avoid confusion you write PEMDAS as PE(MD)(AS).
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>>7809139
You don't even the brackets around 6/2 to remove the ambiguity.
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>>7809166
If I had my own secret society of mathematicians the operations rules would be like this:

1 Evaluate parentheses
2 If the expression is ambiguous, smack the person who wrote it until they add more parentheses
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>>7809224
retards will still think one comes before the other
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>>7809224
Wow, do people really not know order of operations? I am not American but this is the most basic law of math
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>>7807552
6/[2(1+2)]=1
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I hate idiots who carry out 2* prior to divide although its external to the parenthesis
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>>7807552
I gotta minutephysics you idiots? Ok.
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6/2*(2+1)
(6)*(1/2)*(3)

9

bazoople
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>>7807552
Since 2(1+2) isn't like (2(1+2)), I'm thinking that 6/2 is separate than (1+2).

Therefore, I'd say it's 9
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It's 1. Stupid fucks. No one uses a fucking division sign, we use a slash so it's blatantly clear.
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6/(2(1+2))
6/(2(3))
6/(6)
1
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>>7810008
Oh honey, that's about two levels of abstraction beneath the question.
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6/2(1+2)
>Distribute
6/(2+4)
6/6
>Solve
1
>Voilà
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>>7810055
What?
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>>7810200
I suck huge cock
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Looks like it comes out to 9
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6/2(1+2)
6/2+2
3+2
5

Learn to BODMAS fucks
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6÷2 is a coefficient of (1+2)
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>>7807552
Which way are you interpreting that?
A or B?

Personally when I look at it, I see A.
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>>7810335
kek, murrican schooling
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>>7810224
Nigga what the fuck kinda answer is that
How do you go through something step by step and fuck up so badly
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6/2(1+2)
6/2+4
3+4=7

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>>7807552
The answer is "Stop using retarded notation and learn how to write mathematical formulas properly, you fucking faggot. "
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>>7807552

What I learned back in middle school: / and * are on the same priority level, just like + and - are: if there are no brackets, simply start from the left.

I always thought it's obvious to do it this way and never encountered any problems with it until threads like this started popping up.
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>>7809310
>I am not American
You dodged a bullet there, lad.
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>>7809310
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>>7810502
You are literally retarded.
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>>7807610
>using a Casio
>not a superior TI

Basically it is PEMDAS left to right. The operations inside the parenthesis are done first, then if there are no signs between the paranthesises and a number it counts as multiplication. The M and D have equal priority, so does the A and D. You work left to right while applying the priority rules as the apply, and bam, you just learned what you should've learned in grade school.
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>>7810860
>>7810864
Common core is a joke.
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>>7810893
Also an experimental brainwashing tool
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>>7810893
What do either of these pics have to do with common core? Is common core just a code word for stupid teachers?
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>>7807561
>>7807573
BTFO fucking arsehole
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9

i didnt even do maths after school lol
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>>7809224
I fucked it up the first time around because it's physically next to the 2. You evaluate (1+2), which is obvious. The trick in the image is that they put it right next to the 2, so if you've working quickly you will multiply 2*3 and get six.
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>>7807552
what nobody seems to be pointing out is that isn't a division. that's a modulus, which has the same priority as multiplication and division but a different output.

6%2(1+2)
(6%2)(3)
(0)(3)
0
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distribute the 2 faggots
=6/2+4
=3 + 4
=7
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>>7810970
Yes, see >>7809211
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>>7810502
>>7810987
How the fuck do you retards get 4?
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0.999999999.......
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>>7811039
= 1

Use geometric progression.
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>>7810971
kek
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>>7810987
Actually if you did it that way it'd be

6/[2(1+2)]
6/(2+4)
6/6
=1
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>>7810893
Neither of those are from Common core, retard
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>>7807627
3 ↑ ↑ 3
$3^{3 ^ 3}$
$3^{27}$
7625597484987
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>>7807552
Dear god I can't believe people are actually arguing over this.
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>>7807579
I hope you do realise how retarded your statement was. Otherwise please kindly kill yourself.
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>>7807552
http://www.ise.ncsu.edu/jwilson/files/mathsigns.pdf
The question is incorrect and has been for several years
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>>7811390
page number pls
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>>7811551
17, obelus shouldn't be used as a division symbol according to ISO standards.
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>>7811558
I believe that it shouldn't be used as a ratio symbol, given the fact that it was posted exactly after explaining what symbol to use as a ratio.
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>>7811565
Negative, each newline is a new note. And, well, to confirm you can just look at the left columns of the table and notice the obelus is missing from the division operator cells.
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Remember how PEMDAS is from left to right?

6/2(1+2)
First parentheses
6/2(3)
Then you divide because its left of the multiplication
3(3)
then you multiply
9

Do you people remember the basic series formula n/2(n+1) ??

n/2 is a coefficient of (n+1)

Similarly, 6/2 is a coefficient of (2+1).
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>>7811390
>>7811558
>>7811928
Doesn't change the question, really.

[eqn]6/2(1+2) = ?[/eqn]
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>>7810893
But I thought common core was the strategy used to gain the answer of 9 here?
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Lol, troll. People see the division sign and are wondering which order in which you add/divide. Not enough information to solve.
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>>7812622
That's the intention, yes. But its very structure encourages retarded logic.
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Prefix or Postfix, there is no Infix.
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>>7809602
yup, love this video also
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>>7812622
>>7812738
I have no reaction for this
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>>7812738
The estimation is base 10. They're preparing kids for algebra. The correct answer was putting both ways. That's how you avoid the common core point deduction.
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>>7812738
Another way of looking at this is rounding up. You learn in the past.
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Answers is 1 fucking retards. All engineers are sleeping or something?
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>>7812825
75 rounded UP is 80 mate
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>>7810860
>>7810864

Wait WHAT? HAHAHAHA
Is this even real? How could ANYONE defend this shit?
Tell me, seriously, how does this even have sense???
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>tfw wasted an hour reading about this new common core shit, and while I do understand the sense behind it it's still odd to me
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>>7812622