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# Maths illusions watch

the math man is here
numbers war started
LOL! I'm a girl and I'm a natsci not a mathmo!
2. (Original post by Lozza)
haha ok, didn't realise he actually knew he was being dumb. it really does look like something my little sister would write down tho
you evidently dont think much of your sister
(Original post by Lozza)
oh i really hope there's a nice matrix question today.
yey. matrices.
3. (Original post by Lozza)
LOL! I'm a girl and I'm a natsci not a mathmo!

Sorry :embarasse
I did not see it
but great work, really
Sorry :embarasse
I did not sow it
but great work, really
sorry to burst your bubble - but its hardly rocket science - just pointing out that dividing by zero is never a good thing ...
5. (Original post by Zuber)
here's a thread where you can post the best maths illusions. Please feel free to post illusions.

Here's mine. tell me what you think of it

a = b
times both sides by b
ab = b2
minus a2
ab – a2 = b2 – a2
factorise
a(b-a) = (a+b)(a-b)
divide by (b-a)
a = a+b
replace b by a
a = a + a
a = 2a
divide by a
1 = 2

If 1 = 2, the world would end

Maths here too
6. The meaning of life is the opposite of the meaning of death.
Death means not existing, being nothing.
Nothing = 0
0=0/1

Therefore,
The meaning of life = opposite of 0/1 = 1/0
Meaning of life = 1/0 = undefined.
The meaning of life is undefined.

However:
Infinity = undefined = 1/0
Infinity = never ending
Never ending = forever

Diamonds are forever (like the Bond film, ok)
Diamonds = forever = never ending = infinity
As infinity = meaning of life,
Diamonds are the meaning of life

Diamonds = a girl’s best friend (again, like in the movie)
I’m a girl. I’m my own best friend = (therefore I am) a girl’s best friend = diamonds = meaning of life.

Therefore I am the meaning of life.

That's right everyone. Bow down.

I can feel my messiah complex kicking in already.
7. seen it *yawns*
8. (Original post by Zuber)
here's a thread where you can post the best maths illusions. Please feel free to post illusions.

Here's mine. tell me what you think of it

a = b
times both sides by b
ab = b2
minus a2
ab – a2 = b2 – a2
factorise
a(b-a) = (a+b)(a-b)
divide by (b-a)
a = a+b
replace b by a
a = a + a
a = 2a
divide by a
1 = 2

If 1 = 2, the world would end
Moron. You can't divide both by (b-a) because there isn't a (b-a) on each side. Look carefully on the right side and there is (a+b) and (a-b), neither of which is the same as (b-a). All this example proves is how good your eyesight is.

Sorry about that, I've just done a maths test and can't think of anything else at the moment.
9. its wrong. You cant divide.....

DAMNIT sherunsaway you beat me to it!!!!

Old classic

x=0.9reccuring
*10
10x=9.9 reccuring
10x-x
9x=9
x=1

But x also equals 1, meaning that 1 ≡ 0.9reccuring

Im thinking though, could this have the same principle as an ordered pair, in that to fit the quation there are 2 possible values. Actually maybe not, as they dont proooveeach other. Hmm i dunno
10. Oh yeah, lots of ways to do that one...

1/3 = 0.3 recurring

3*(1/3) = 1
But, 3*(0.3 recurring) = 0.9 recurring

is another valid one
11. ^^
thats true, and simpler.

so what is 1.9 reccuring x 2
3.9 reccuring but somewheree at the end an 8 would have jto be present

Might it be

.
3.98?
12. (Original post by sherunsaway)
Moron. You can't divide both by (b-a) because there isn't a (b-a) on each side. Look carefully on the right side and there is (a+b) and (a-b), neither of which is the same as (b-a). All this example proves is how good your eyesight is.

Sorry about that, I've just done a maths test and can't think of anything else at the moment.
Um... yes you can: it's the same as dividing by -(a-b). Admittedly this is not what as been done (the LHS has not been multiplied by -1), but it's still a valid thing to do.
13. ^^
a(b-a) = (a+b)(a-b)
divide by (b-a)
thus his proof is incorrect
14. anyone who says he made a mistake...you're right

anyone who says it's incorrect because of the dividing by zero - you're right as well.

you can't do maths illusions (well any marks i got in that tripos exam might be illusions)
15. 1+1=3 Kaboom!!!!!!!!!!!!!
16. dear god no!!!

if thats true then 2+2=5!!!!!!
17. (Original post by MR_JR)
dear god no!!!

if thats true then 2+2=5!!!!!!
Of course it doesn't, that's completely illogical. Everyone knows that 2+2=∞
18. sorry all. i edited my original post. b2 - a2 = (b-a)(b+a), i was just writing it quickly and so wrote it the wrong way round. . and everyone its an illusion, dont get so worked up (eg lozza).
19. (Original post by Lozza)
i've realised i can't even post what i wanted to because they don't have the correct symbols so i'll post in words
e^i(theta) = cos(theta) + isin(theta)
woo
which gives my fave equation
e^i.pi +1 = 0
You can either use the tex tags or the symbols above the input box
20. (Original post by El Chueco)
you evidently dont think much of your sister
my sister is 11.

i'm allowed to get worked up. i've been drunk for thelast 5 hours. very very paifnull y drunk.

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