# $\frac{100-100}{100-100}$ =2

Suppose a problem be given that $\frac{100-100}{100-100}$ =?

Couldn't we solve it in this manner?

$\frac{100-100}{100-100}$

= $\frac{10^2-10^2}{10(10-10)}$

= $\frac{(10+10)(10-10)}{10(10-10)}$

Cancelling 10-10 from the numerator and the denominator we get,

$\frac{10+10}{10}$

= $\frac{20}{10}$

=2

Note by Anik Mandal
7 years, 2 months ago

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You divided by 0 by canceling 10-10, but division by zero is undefined.

NO YOU CANCELLED (10-10) WHICH IS 0 AND DIVISION BY 0 IS NOT DEFINED

- 7 years, 2 months ago

yeah i was alarmed though

- 7 years, 2 months ago

Could anyone give me an exact reason as to why division by 0 is undefined........

- 7 years, 2 months ago

Dividing by 0 is not defined because if you divide 0/0 you can get any value from negative infinity to positive infinity because any number into 0 is 0. and if the numerator is non-zero then no number can satisfy the satisfy the equation

- 7 years, 2 months ago

Thanks for your explanation!

- 7 years, 2 months ago

If you divide by zero then all numbers become equal and this is thus meaningless, so division by zero is defined to be undefined!! If division by zero was defined then almost entire mathematics would crumble down

- 7 years, 2 months ago

Well, thanks!

- 7 years, 2 months ago

Welcome anik :)

- 7 years, 2 months ago

try to divide a cake made of air. it is like you cannot divide that does not a value or just "nothing".. :)

- 7 years, 2 months ago

Wrongggg.... …

- 7 years, 2 months ago

Dividing zero by zero is not defined...Π™

- 7 years, 2 months ago

Dear friends why u getting problem in this is because u underestimated or forgot one thing that is

10^2=100. And -10^2 is also 100 so u must take. Both under consideration

- 7 years, 1 month ago

10-10 and 10-10 cannot be cancelled cause 0 and 0 cannot be cancelled

- 6 years, 3 months ago

10-10=0 in maths /0 is error

- 6 years, 3 months ago

Is $\lim _{ x->a }{ f(x) } =\frac { 0 }{ 0 }$ defined? If yes, why so?

- 6 years, 1 month ago

how its possible...?

- 6 years ago

Diving by zero is the wrong step

- 5 years, 11 months ago

no.....you cannot divide the numerator and denomenator with zero

- 5 years, 11 months ago

no can't do so my dear , because 0 (= 10-10) can't be cancelled from the numerator & denominator , and if we do so then we will get the answer which we ourselves can't explain

- 5 years, 10 months ago

Oh yes you are correct my dear :p

- 5 years, 10 months ago

Well, 100-100=0, so from the very start you're kinda messing yourself over :P

To the point where no step doesn't divide by zero until (10+10)/10

It took me a while to notice though.

- 5 years, 10 months ago

While cancelling, you are assuming that $\dfrac{0}{0} = 1$ which is not the case

- 5 years, 9 months ago

why not 100-100/100-100=0/0

- 5 years, 4 months ago

Gud

- 7 years, 2 months ago

WHAT DO YOU MEAN BY GOOD ? IT IS COMPLETELY WRONG!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

- 7 years, 2 months ago

Hey its wrong i too know it...practically its not possible but theoretically its possible.

- 7 years, 2 months ago

Even theoretically it's impossible since it uses division by zero, which as we all know is undefined.

Theoretically possible? IT's using division by zero. the main step is not possible even! how can it be theoretically possible,,lol

- 7 years, 2 months ago

NO NOT EVEN THEOROTICALLY. THE STEPS HE PERFORMED ARE ABSOLUTELY WRONG. HE DIVIDE BY 0

- 7 years, 2 months ago

How can it be theoretically possible, Shrey?????

- 7 years, 2 months ago