
1=2 proof
Hey, swim is new here and is wondering if someone could direct him to the classic 1=2 proof? Thanks.
 JaneFairfax
 Legendary Member
Re: 1=2 proof
Why do you want to learn incorrect proofs? Much better if you just concentrate on learning correct proofs. That might help you pass your exams.
Q: Who wrote the novels Mrs Dalloway and To the Lighthouse? A: Click here for answer.
 bobbym
 Administrator
Re: 1=2 proof
Hi dreamalot;
I'm afraid Jane is right about learning correct proofs but if you are determined to see this, here is a link that I know of. http://en.wikipedia.org/wiki/False_proof
Last edited by bobbym (20090515 15:32:18)
In mathematics, you don't understand things. You just get used to them. I have the result, but I do not yet know how to get it. All physicists, and a good many quite respectable mathematicians are contemptuous about proof.
Re: 1=2 proof
That's the first false proof I've found the fault in
Division by 0.. (ab), where a=b
 JaneFairfax
 Legendary Member
Re: 1=2 proof
Here is another “proof” that 1 = 2, one that doesn’t make use of division by 0.
Last edited by JaneFairfax (20090613 21:05:48)
Q: Who wrote the novels Mrs Dalloway and To the Lighthouse? A: Click here for answer.
 bobbym
 Administrator
Re: 1=2 proof
Hi Jane;
I know you are not posing this as a problem but
Line 1 identity Line 2 identity
As near as I can figure the problem is with the third statement, the taking of the square root of both sides.
which is only true for
Last edited by bobbym (20090614 16:17:15)
In mathematics, you don't understand things. You just get used to them. I have the result, but I do not yet know how to get it. All physicists, and a good many quite respectable mathematicians are contemptuous about proof.
 ganesh
 Moderator
Re: 1=2 proof
Here is another: But this proves 2 > 3.
3 < 2
Character is who you are when no one is looking.
Re: 1=2 proof
hi friends im just new member of this website..i love math very much. i join here just to know what makes math simple and remembering all about math...i hope somebody can help me in this. thanks.
 bobbym
 Administrator
Re: 1=2 proof
Hi amhore;
Jane wrote:Why do you want to learn incorrect proofs? Much better if you just concentrate on learning correct proofs. That might help you pass your exams.
She is still right.
About half way down the page. click me for false proofs
Last edited by bobbym (20090805 03:32:39)
In mathematics, you don't understand things. You just get used to them. I have the result, but I do not yet know how to get it. All physicists, and a good many quite respectable mathematicians are contemptuous about proof.
Re: 1=2 proof
Hi friends i am just a new member of this web site.i love math very much. i am intrested in incorrect proof.
 bobbym
 Administrator
Re: 1=2 proof
In mathematics, you don't understand things. You just get used to them. I have the result, but I do not yet know how to get it. All physicists, and a good many quite respectable mathematicians are contemptuous about proof.
Re: 1=2 proof
hi manzil i like the message that you so try to seek or solve my given problem proof that 1=0: its just a play dont be too serious in everything remember that my is not hard just play it around so you can learn everything....ok just relax friends..
Re: 1=2 proof
amhore13 wrote:can you proof 1=0
pls tell me how it will get
 bobbym
 Administrator
Re: 1=2 proof
Hi santhosh;
JaneFairfax wrote:Jane wrote:Why do you want to learn incorrect proofs? Much better if you just concentrate on learning correct proofs. That might help you pass your exams.
She is still right.
She is even more correct!
Welcome to the forum!
In mathematics, you don't understand things. You just get used to them. I have the result, but I do not yet know how to get it. All physicists, and a good many quite respectable mathematicians are contemptuous about proof.
 jk22
 Member
Re: 1=2 proof
Hi,
we have not 1=2, except if units are e.g. $ and £ in the year (to find, e.g. in the y 1976, or 1978 http://www.miketodd.net/encyc/dollhist.htm)...1£=2$ were at some time of the story of humanity.
but we were allowed to write
2 is equivalent to 0 (modulo 2)
divide by 2 and
1 is equivalent to 0 (modulo 1).
Last edited by jk22 (20100807 06:51:45)
 bob bundy
 Moderator
Re: 1=2 proof
Actually, I don't think there's any harm studying 'false' proofs as long as you're aware that there is something wrong with the proof.
That way you learn something about what is allowable in a proof and what isn't.
In the example that started this thread, for example, you should learn that dividing by zero is not acceptable in algebra.
You cannot teach a man anything; you can only help him find it within himself..........Galileo Galilei
 jk22
 Member
Re: 1=2 proof
Hi,
yes, or 0^0.
Studying false proof can help not making them. Some pitfall are :
a) right deduction, but hypotheses aren't (Sometimes proven after), hence we can deduce nothing
b) the proof uses the result to be proven
Last edited by jk22 (20100809 00:09:14)
Re: 1=2 proof
plz help me 2 find out the wrong step:all digits are equal just putting values of x,y s1) x.y=x.y s2) x^2x(x+y)=y^2y(x+y) s3) x^22x(x+y)/2+{(x+y)/2}^2 = y^22y(x+y)/2+{(x+y)/2}^2 s4) {x(x+y)/2}^2 = {y(x+y)/2}^2 s5) x(x+y)/2 = y(x+y)/2 s6) x=y
 bob bundy
 Moderator
Re: 1=2 proof
hi sur_arijit01
It looks to me like S4 > S5 is the faulty step.
Just because a^2 = b^2 you may not conclude that a = b eg. 9 = 9 but + 3 is not equal to 3
But if you write
s5) x(x+y)/2 = (y(x+y)/2)
then you get x + y = x + y which seems more reasonable.
Bob
footnote: When I'm trying to track down an algebraic error the following sometimes works.
Choose a value for x and another for y. (Best to avoid 0 and 1 here)
If the value of the LHS = RHS then there's a strong chance the steps to that point are OK.
When LHS not = RHS you know a false step has occurred.
Last edited by bob bundy (20110507 04:45:09)
You cannot teach a man anything; you can only help him find it within himself..........Galileo Galilei
Re: 1=2 proof
You can proof substitution with number, no need to let x=y.
10² = 100 (right) 10²10²=100100 (1010)(10+10)=10(1010) So, (10+10)=10 20=10 2=1
 bobbym
 Administrator
Re: 1=2 proof
Hi joker30;
Welcome to the forum!
That is a little bit of a twist!
In mathematics, you don't understand things. You just get used to them. I have the result, but I do not yet know how to get it. All physicists, and a good many quite respectable mathematicians are contemptuous about proof.
 bob bundy
 Moderator
Re: 1=2 proof
hi joker30
OK, but it's still a case of:
in post #18, I wrote:In the example that started this thread, for example, you should learn that dividing by zero is not acceptable in algebra.
except substitute 'number calculations' for 'algebra'. Bob
Last edited by bob bundy (20110620 03:00:55)
You cannot teach a man anything; you can only help him find it within himself..........Galileo Galilei
Re: 1=2 proof
ganesh wrote:Here is another: But this proves 2 > 3.
3 < 2
You're missing required grouping symbols, ganesh.
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