A short problem, help please!

[diamondfox]

Right, my first post, I'll say, "hi" to everybody for a start.

Hello.


Now for the problem, I would like somebody to come up to me with an answer fast since I only have 4 hours left. = (.

!!!!The numbers in the first statement in the bracket are, powers!!!!

1(2') - 1(2') = 1-1
(1+1)(1-1) = 1-1
1+1 = 1
2 = 1

Now according to our math teacher, the first statement is correct while the other 3 are wrong. :eek:

Now help me??!!

[pyr0x90]

Sry i don't know what ur asking
but the second one i don't get

(1+1)(1-1)=1-1
2*0=1-1
0=0
so i dont see how thats wrong. but if u specify the question in time maybe i can help.

[diamondfox]

Man, don't ask me, the first and second are correct (according to me) but then again I have no idea how a teacher can come up with something like this.

[pyr0x90]

maybe she means that they dont mean the same as the first. what class are u in?

[diamondfox]

Well 1st year of high school (in europe, in slovenia) what that means in america I have no clue.

I'm 14 years old, and I started school at 6, also I skipped no grade.

[pyr0x90]

for your age, idk what she want u to get out of this problem. It seems like just a powers example and what they are

[diamondfox]

K, I'll post after class. I'll see what she's actually trying to say by this.

[OfficeShredder]

The point of this example is that to reach the third step, you divided both sides by (1-1), or 0. This isn't allowed (3*0=2*0, so 3=2?) Specifically, as you go higher up in math, zero will take on more subtle forms (1-1 being a not so subtle form, but certainly more subtle than simply 0) and you need to be on the lookout for them