No, they are the same thing. You just drop the '*' sign as mathematicians looove shortcuts lool
You don't assign a bracket to a number, you multiply a bracket by a number.
Poll: 6÷2(1+2)
- Thread starter Barks
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No, they are the same thing. You just drop the '*' sign as mathematicians looove shortcuts lool
You don't assign a bracket to a number, you multiply a bracket by a number.
Soldato
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The 'B' in BODMAS refers to everything strictly inside the bracket, not outside it, hence the 2 outside counts as multiplication.
The poll however, uses / instead of ÷, which increases confusion further.
Since it's all written on one line, when you expand the brackets you have to expand thus:
(6/2)(1+2)
The only way you could expand to 2(1+2) would be if the 6 were on a line above. But it's not written that way, right?
BODMAS encourages bad notation.
The implications that division takes precedence over multiplication, and that addition takes precedence over subtraction are wrong. They are the same operations, and relying on BODMAS to interpret badly written expressions like the one in the OP is ridiculous.
We should stop teaching BODMAS and start teaching correct notation from the start.
/edit:
They mean exactly the same thing. That's why the expression is so ambiguous.
The implications that division takes precedence over multiplication, and that addition takes precedence over subtraction are wrong. They are the same operations, and relying on BODMAS to interpret badly written expressions like the one in the OP is ridiculous.
We should stop teaching BODMAS and start teaching correct notation from the start.
/edit:
They mean exactly the same thing. That's why the expression is so ambiguous.
Soldato
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Nicely said, and the point I was trying to make above.
No. the way it has been originally written with the ÷ rather than / means it can be written on the same line and is calculated as I showed to give the answer of 1. You would only need to put the 6 on the line above if / was used instead of ÷.
The error that people are falling into using BODMAS is they are applying it to early. They have not fully expanded the brackets before applying the BODMAS rule (they have not multiplied the result of the bracket by the 2 associated with it).
Soldato
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No the equation does not say 6/2*(1+2), it says 6/2(1+2). The 2 is, literally, attached to the bracket without an operator. In terms of order, n(p) has a higher precedence than n*(p).
These have the same order
2x
2*x
2*(x) == 2*1(x)
This has a higher order
2(x)
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What? np is another way of writing n*p. n(p) in this case does not mean function n with argument p. It just means np.
Brackets mean you work out the stuff inside first, not that you have to apply the stuff outside to the stuff inside first.
At least that's what I learned.
No,no,no. That doesn't even make sense. If there is no operator between the 2 and the bracket then it's not maths! There has to be an operator, which is multiplication, but because of shorthand, we don't write it, it's assumed, so they are one and the same.
It's like saying ab isn't the same thing as a*b - it's a ridiculous claim.
Soldato
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The 2 is not inside the brackets though, which what the D in BODMAS covers. Anything outside the brackets must be treated separately. Hence we have the following:
Brackets:
6÷2(1+2) = 6÷2*3
Division:
6÷2*3 = 3*3
Multiplication:
3*3 = 9
Ambiguous question is ambiguous...
If I saw 6/2(1+2) id be assuming the someone is trying to write the following
__6__
2(1+2)
Just goes to show the need for clear brackets when entering an eqn into a comp, whoever writes such an ambiguous eqn is asking for trouble!
If I saw 6/2(1+2) id be assuming the someone is trying to write the following
__6__
2(1+2)
Just goes to show the need for clear brackets when entering an eqn into a comp, whoever writes such an ambiguous eqn is asking for trouble!
I have never, ever seen that written in any text book, anywhere.
Where did you get that?
I did it and got 9. Just use BIDMAS. If you want proof, Wolfram seems to agree:
http://www.wolframalpha.com/input/?i=solve+6/2(1+2)
If the answer is meant to be 1, then someone needs to learn how to use brackets properly
.
http://www.wolframalpha.com/input/?i=solve+6/2(1+2)
If the answer is meant to be 1, then someone needs to learn how to use brackets properly
.
Soldato
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You don't have to assume anything, because BODMAS should be invoked under such cases. If someone wanted to write down what you assumed, in a single line, they should have wrote it as follows:
6/(2(1+2))
Precisely.
3rd answer to poll: Use correct notation plssxlzxozossxzxzzz zomg
i know that, but when entering / on a computer, people tend to use this as a shortcut for displaying a fraction, instead of a divide symbol. Hence its still ambiguous.
haha!
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Soldato
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When ever you write a number, ANY number, it is short hand notation for 1(x) == x ie one lot of that number
1+2=3 == 1(1) + 1(2) = 1(3)
one one plus one two equals one three.
Which is NOT the same as saying
1*1 + 1*2 + 1*3
one times one plus one times 2 plus 1 times three
For instance, in spoken language you would say 'I have one fish' or 'I have three fish' NOT 'I have one times a fish' or 'I have three times a fish'
(three fish) - a singular quantity composed of three fish
three times (a fish) - 3 quantities of a single fish
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