Galileo Galilei

"Mathematics is the language with which God has written the universe."

Paul Dicac

"God used beautiful Mathematics in creating the world"

Andre Weil

"God exists since mathematics is consistent, and the Devil exists since we cannot prove it."

Maryam Mirzakhani

"The beauty of mathematics only shows itself to more patient followers."

Stefan Banach

"Mathematics is the most beautiful and most powerful creation of the human spirit."

Sunday, April 11, 2021

What happens when you divide something by zero?


What is the value of 1 ÷ 0 or 2 ÷ 0 or any number ÷ 0? Is it 0 or anything else?
Let's analyze it.


Let's examine it for 1 ÷ 0.


We get,

....................
1 ÷ 100 = 0.01
1 ÷ 10 = 0.1
1 ÷ 1 = 1
1 ÷ 0.1 = 10
1 ÷ 0.01 = 100
1 ÷ 0.001 = 1000
1 ÷ 0.0001 = 10000
1 ÷ 0.00001 = 100000
....................
1 ÷ 0.000000000000000001 = 1000000000000000000
...................
1 ÷ 0.0000000000000000000000000000001 = 10000000000000000000000000000000

As we divide by closer and closer to 0 the division result gets bigger and bigger.

So, we can say that when we divide exactly by 0, the result will be the largest possible value i.e. ∞

So, 1 ÷ 0 = ∞ (when we approach from ∞ to 0)

 
But, if we approach from -∞ to 0,

..................
1 ÷ -100 = -0.01
1 ÷ -10 = -0.1
1 ÷ -1 = -1
1 ÷ -0.1 = -10
1 ÷ -0.01 = -100
1 ÷ -0.001 = -1000
1 ÷ -0.0001 = -10000
1 ÷ -0.00001 = -100000
....................
1 ÷ -0.000000000000000001 = -1000000000000000000
...................
1 ÷ -0.0000000000000000000000000000001 = -10000000000000000000000000000000

As we divide by closer and closer to 0 the division result gets smaller and smaller.

So, we can say that when we divide exactly by 0, the result will be the smallest possible value i.e. -∞

So, 1 ÷ 0 = -∞ (when we approach from -∞ to 0)


So, we get two possible values for 1 ÷ 0. They are ∞ or -∞. By the definition of division, a division must have only one result and can not have two or more results. Here, we have two possible results for division and we don't know which of them is the correct answer. So, 1 ÷ 0 is not defined by the definition of division. That's why we say 1 ÷ 0 is undefined.


÷ 0 = undefined


Similarly, 

÷ 0 = undefined

÷ 0 = undefined

÷ 0 = undefined

............................

Any Number ÷ 0 = undefined


But, we have another problem for 0 ÷ 0. We'll discuss that in another post. So, the division of any number by 0, except 0  ÷ 0 is undefined.


If you have any question, feel free to ask.