Eric's collar
Eric's collar
I was referring to the question. I know x^2=9 has 2 answers but in this case such as 2+2, there is only one answer and that is 5.
Poll: 6÷2(1+2)
- Thread starter Barks
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I was referring to the question. I know x^2=9 has 2 answers but in this case such as 2+2, there is only one answer and that is 5.
2 = 1
Let a = b, then a^2 = b^2.
This means a^2-b^2=0.
Factoring the left yields (a-b)(a+b)=0.
This means (a-b)(a+b)=a^2-b^2.
But since b=a, You can say that a^2-b^2 = a*b-b^2.
Therefore (a-b)(a+b)=a*b-b^2.
Factoring the right yields b*(a-b).
Therefore (a-b)(a+b)=b*(a-b).
Dividing by a-b gives a+b=b.
But since a=b, we have b+b=b, or 2b=b.
Dividing by b gives 2=1.
Let a = b, then a^2 = b^2.
This means a^2-b^2=0.
Factoring the left yields (a-b)(a+b)=0.
This means (a-b)(a+b)=a^2-b^2.
But since b=a, You can say that a^2-b^2 = a*b-b^2.
Therefore (a-b)(a+b)=a*b-b^2.
Factoring the right yields b*(a-b).
Therefore (a-b)(a+b)=b*(a-b).
Dividing by a-b gives a+b=b.
But since a=b, we have b+b=b, or 2b=b.
Dividing by b gives 2=1.
Soldato
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Nope, can't. I've tried. I understand the argument very well and for me it's not the divisor. Trouble is my old Engineers brain will always take the bracketed item as a single term. Using large equations a lot I tend to break them into usable chunks, yeah I can see the other result, but given a choice I see 1 (or dead people).legitimately expand 3(2+1) and you'd arrive at the correct answer
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In that case yes, but it hardly applies in generality does it?
Well it was good being part of a very active thread. Now I depart..
+1
Dividing by zero fail
(dividing through by a-b, when a = b!)As for OP, I say 9. Brackets first, then multiplication/division sweeping from left to right.
From where I wrote on your line of poop. if a = b
then a - b = 0
therefore when you divide by a-b you are dividing by 0, you can't do it.
Game set match. Thanks for coming.
Oh and Hi-Five Dave.
Soldato
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I will say this thread is heading where they all tend to, which is quite a funny observation for me.
The Unreal Tournament "double kill" voice sprang to mind then
Hugh - MILLY - ation.
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PERFECKT
Soldato
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Were you around for the 0.999...=1 thread?
Oh I avoid them usually, the headaches.
Just a message for some of those who are poking fun at others.
There are two solutions, differing in interpretation of the ambiguous expression.
If you can't understand this then refrain from accusing others of lacking intelligence. Any spastic can apply some Kindergarten mathematical operating rule without really having a grasp on the subject. The argument being put fourth by those who are qualified to debate this is that in practical application of mathematics either interpretation may be more appropriate given the context of the problem at hand, although the expression is still irrefutably ambiguous.
There are two solutions, differing in interpretation of the ambiguous expression.
If you can't understand this then refrain from accusing others of lacking intelligence. Any spastic can apply some Kindergarten mathematical operating rule without really having a grasp on the subject. The argument being put fourth by those who are qualified to debate this is that in practical application of mathematics either interpretation may be more appropriate given the context of the problem at hand, although the expression is still irrefutably ambiguous.
/thread