I know how to use 0 < x−a < δ ⇒f(x)−L < ɛ when "a" is some fixed real number, but what do we do when "a" = ∞? Can we still use the definition 0 < x−a < δ ⇒f(x)−L < ɛ?

I know how to use 0 < x−a < δ ⇒f(x)−L < ɛ when "a" is some fixed real number, but what do we do when "a" = ∞? Can we still use the definition 0 < x−a < δ ⇒f(x)−L < ɛ?
Hi Utopian
The definition changes for infinite limits
there such that if then
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