Question

why is this true? I mean, why is a modulus function giving an negative x?

Answer 1

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Answer 2

I understand why x if x >= 0
but I cant wrap my head around a modulus function giving a negative value: -x if x < 0

Answer 3

It’s value would be -x , becausethe negative of a negative is positive.

Answer 4

sqrt(x^2 ) asks for the positive root of x^2 . Therefore, it’s equal to the absolute value of x. The piecewise function is the definition of absolute value; keep it unchanged for positive x, and multiply by -1 for negative x.

Answer 5

There is no modulus function.

Edit: ok, TIL "modulus" is yet another word for "absolute value"

In which case, as others have noted, it's not returning a negative number; if x<0 then it's returning a negative negative (positive) number.