proof for 1=2 (1 Viewer)

[Estel]

You can't square and then take the square root of....
otherwise all neg. become pos

 

[Zarathustra]

Why is it then that certain actions are prohibited?

Who says all negative numbers aren't positive
What's the theory behind you can't take the square then the square root.

 

[CM_Tutor]

sqrt(x^2) = |x|

 

[Giant Lobster]

what he did doesnt follow logically
he treated 4 like a variable

sqrt4 = 2 always
sqrtx^2 = |x|
x^2 = c^2 (c constant)
x = c or -c

 

[JamiL]

no
eg x^2=9
therefore x= 3/-3
but (x^2)^(1/2)=3
therefore 3=3
u assume the number is positive in a sqare root unless otherwise stated
therefore if i right -(x^2)^(1/2)=3
therefore -3=3
and that is rong

 

[Xayma]

Originally posted by Giant Lobster
what he did doesnt follow logically
he treated 4 like a variable

at least it looks more logical then 1=2. I deliberatly didnt use sqrt and used ^1/2 because it doesnt imply a sign.

 

[Giant Lobster]

yeah.
the absence of (-) implies (+)
well anyway, i fell for that ^1/2 thingy in yr 11 so aha

 

[haz_it_all]

i can show that 1 is rounded up

1/3 = 0.3333333...
2/3 = 0.3333...+ 0.3333... = 0.6666666
3/3 = 0.3333...+ 0.3333... + 0.3333... = 0.9999999
this means 1 is actual equal to 0.999999

 

[Estel]

actually...
1 is equal to 0.99999...

 

[JamiL]

yep 1=0.99999999999999999.... its the same thing