MathsManiac wrote: » You've made the puzzle for too transparent! You need to try to bury the division by 0 more, so that it's a bit harder to spot. Try this: let a=b=1 multiply both sides by b: ab = b^2 subtract a^2 from both sides: ab - a^2 = b^2 - a^2 Factorise: a(b-a) = (b-a)(b+a) Cancel the common factor: a = b+a But we already know that a=b=1: 1 = 1+1 That is: 1 = 2.
TripleAce wrote: » (b-a)/(b-a)
McSeamus ORiley wrote: » For all n, n/n = 1 at n=0 0/0 = 1 so 0/0 + 0/0 = 2 but 0/0 + 0/0 = (0+0)/0 = 0/0 =1 giving 1=2 add 1 to both sides 2=3 but 2=1 so 1=3 likewise 1=4 1=5 1=6 ..... Therefore for all n, n=1 :pac:
McSeamus ORiley wrote: » Dumbass
Sean_K wrote: » 1^1 = 1 1^0 = 1 => 1=0 :pac::p
LeixlipRed wrote: » The whole point of a fallacy is that you don't explicitly state the mistake in the second line of the "proof"
Sean_K wrote: » Conjecture: McSeamus ORiley==e05bf05a
LeixlipRed wrote: » Much more subtle this time Here's another one that doesn't involve division by 0. 4 - 6 = 1 - 3 4 - 6 + 9/4 = 1 - 3 + 9/4 (2 - 3/2)^2 = (1 - 3/2)^2 2 - 3/2 = 1 - 3/2 2 = 1
LeixlipRed wrote: » Here's another one I'd forgotten about as well. The derivative of x^2 is 2x using the Power Rule. But x^2=x+x+....+x (x times) e.g 4^2=16 or 4+4+4+4=16. The derivative of x is one so the derivative of x^2=x+x+...+x (x times) is 1 added up x times or just x! There are two things wrong with this "proof" by the way.
TripleAce wrote: » a=b therefore 0=b-a Now we divide both by b-a: 0/(b-a) =(b-a)/(b-a) and so: 0 = 1 Why?
Michael Collins wrote: » Too obvious! But better than the divide by zero one...It's the fourth line here that has the false step - need to take account of the possiblity of the root being negative...which it turns to be in this case Well x is a variable, so the amount of x's on the RHS will be a function of x, so you cannot just assume it's constant. Not sure about the second error, is it to with the fact derivatives only operate on functions, and the RHS isn't a proper function? How about this one: 1 = sqrt (-1 * -1) 1 = sqrt(-1)*sqrt(-1) 1 = i * i 1 = -1
Michael Collins wrote: » How about this one: 1 = sqrt (-1 * -1) 1 = sqrt(-1)*sqrt(-1) 1 = i * i 1 = -1