WHAT IS SGN (2.5) BY DEFINITION?

sgn(2.5)

= $\dfrac{2.5}{|2.5|}\\ = 1$

               -1 when x< 0

sgn(x) = undefined when x = 0

              1 when x > 0

https://www.desmos.com/calculator/hnpqmpeny5 

A graph of sgn(x).

If you didn't ask this question I wouldn't do research about sgn(x)....... Anyways, Thank you!!

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