## Infinity Symbol

The infinity symbol is a mathematical symbol that represents an infinitely large number.

The infinity symbol is written with the Lemniscate symbol:

∞

It represents an infinitely positive big number.

When we want to write an infinitely negative number we should write:

-∞

When we want to write an infinitely small number we should write:

1/∞

## Is infinity a real number?

Infinity is not a number. It does not represent a specific number, but an infinitely large quantity.

## Infinity rules & properties

Name Key type Positive infinity ∞ Negative infinity -∞ Infinity difference ∞ - ∞ is undefined Zero product 0 · ∞ is undefined Infinity quotient ∞ / ∞ is undefined Real number sum x+ ∞ = ∞, forx∈ℝPositive number product x· ∞ = ∞, forx>0## How to type infinity symbol on keyboard

Platform Key type Description PC windows Alt+236 Hold the ALTkey and type236on the num-lock keypad.Macintosh Option+5 Hold the Optionkey and press 5Microsoft word Insert >Symbol > ∞Menu selection: Insert >Symbol > ∞Alt+236 Hold the ALTkey and type236on the num-lock keypad.Microsoft excel Insert >Symbol > ∞Menu selection: Insert >Symbol > ∞Alt+236 Hold the ALTkey and type236on the num-lock keypad.Web page Ctrl+C, Ctrl+V Copy ∞ from here and paste it in your web page. Ctrl+C, Ctrl+V Copy ∞ from here and paste it in your Facebook page. HTML ∞ or ∞ ASCII code 236 Unicode U+221E LaTeX \infty MATLAB \infty Example: title('Graph to \infty') ## Infinity in set theory

Aleph-null () is the infinite number of elements (cardinality) of the natural numbers set ().

Aleph-one () is the infinite number of elements (cardinality) of the countable ordinal numbers set (ω

_{1}).

## See also