Is infinity always positive?

Question

If we have ∞, is it always implied to be positive (and we have to write -∞ for it to be negative) or can ∞ mean either positive or negative infinity?

Answer 1

 The infinity symbol means positive infinity. Of course, negative infinity comes up in math. Just put a minus sign on the symbol. 

Answer 2

right,infinity always positive

Answer 3

Infinity ∞ is being endless

Answer 4

It can be "negative" when the measurement system has an arbitrary zero value (no absolute zero, only a relative zero).  The negative is just an arbitrary sign so has no real effect on the idea of infinity, and it could be that the entire system is all negative, if the zero value is so selected, and thus any infinity in that system would have to be negative.

Infinity is infinity.  What direction (a "sign") you assign to it is a choice that has no impact on the fact that the thing is infinite.

Answer 5

i've counted to infinity , twice . 

Answer 6

https://www.math.wisc.edu/~dymarz/171/epsdelta.pdf

Answer 7

It's considered to be positive, unless otherwise indicated.