Infinity is not in the set of Real numbers so subtraction with these symbols is undefined.
Inf – Inf shows up in the context of calculus as an indeterminate form; sqrt(x-1) – sqrt(x+1) is a difference of two functions that each grow without bound (to infinity) as x grows without bound (to infinity), however, it can be shown that their difference as x grows to infinity is finite (0).
But other pairs of functions lead to different results. Depending on the f(x) – g(x), as x goes to infinity this can approach other finite numbers, or positive infinity, or negative infinity. Hence the name, indeterminate form.
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Gone
Nov 03, 2020 at 03:40PM EST in reply to
proteronhysteron
Nov 02, 2020 at 01:56PM EST