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Proposition 43

[0BK] In the case \(x_ 0βˆˆβ„\) and \(lβˆˆβ„\), we divide the definition into two conditions: 1

\(\limsup _{xβ†’ x_ 0} f(x) ≀ l\)

\(\limsup _{xβ†’ x_ 0} f(x) β‰₯ l\)

\(βˆ€ \varepsilon {\gt}0, βˆƒ 𝛿 {\gt}0, βˆ€ x, |x-x_ 0|{\lt}𝛿, xβ‰  x_ 0, x∈ Iβ‡’f(x){\lt}l+\varepsilon \)

\(βˆ€ \varepsilon {\gt}0, βˆ€ 𝛿 {\gt}0, βˆƒ x, |x-x_ 0|{\lt}𝛿, xβ‰  x_ 0, x∈ I, f(x){\gt}l-\varepsilon \)

\(\limsup _{xβ†’ x_ 0^+} f(x) ≀ l\)

\(\limsup _{xβ†’ x_ 0^+} f(x) β‰₯ l\)

\(βˆ€ \varepsilon {\gt}0, βˆƒ 𝛿 {\gt}0, βˆ€ x, |x-x_ 0|{\lt}𝛿, x{\gt} x_ 0, x∈ Iβ‡’f(x){\lt}l+\varepsilon \)

\(βˆ€ \varepsilon {\gt}0, βˆ€ 𝛿 {\gt}0, βˆƒ x, |x-x_ 0|{\lt}𝛿, x{\gt} x_ 0, x∈ I, f(x){\gt}l-\varepsilon \)

\(\limsup _{xβ†’ x_ 0^-} f(x) ≀ l\)

\(\limsup _{xβ†’ x_ 0^-} f(x) β‰₯ l\)

\(βˆ€ \varepsilon {\gt}0, βˆƒ 𝛿 {\gt}0, βˆ€ x, |x-x_ 0|{\lt}𝛿, x{\lt} x_ 0, x∈ Iβ‡’f(x){\lt}l+\varepsilon \)

\(βˆ€ \varepsilon {\gt}0, βˆ€ 𝛿 {\gt}0, βˆƒ x, |x-x_ 0|{\lt}𝛿, x{\lt} x_ 0, x∈ I, f(x){\gt}l-\varepsilon \)

\(\liminf _{xβ†’ x_ 0} f(x) β‰₯ l\)

\(\liminf _{xβ†’ x_ 0} f(x) ≀ l\)

\(βˆ€ \varepsilon {\gt}0, βˆƒ 𝛿 {\gt}0, βˆ€ x, |x-x_ 0|{\lt}𝛿, xβ‰  x_ 0, x∈ Iβ‡’f(x){\gt}l-\varepsilon \)

\(βˆ€ \varepsilon {\gt}0, βˆ€ 𝛿 {\gt}0, βˆƒ x, |x-x_ 0|{\lt}𝛿, xβ‰  x_ 0, x∈ I, f(x){\lt}l+\varepsilon \)

\(\liminf _{xβ†’ x_ 0^+} f(x) β‰₯ l\)

\(\liminf _{xβ†’ x_ 0^+} f(x) ≀ l\)

\(βˆ€ \varepsilon {\gt}0, βˆƒ 𝛿 {\gt}0,βˆ€ x, |x-x_ 0|{\lt}𝛿, x{\gt} x_ 0, x∈ Iβ‡’f(x){\gt}l-\varepsilon \)

\(βˆ€ \varepsilon {\gt}0, βˆ€ 𝛿 {\gt}0, βˆƒ x, |x-x_ 0|{\lt}𝛿, x{\gt} x_ 0, x∈ I, f(x){\lt}l+\varepsilon \)

\(\liminf _{xβ†’ x_ 0^-} f(x) β‰₯ l\)

\(\liminf _{xβ†’ x_ 0^-} f(x) ≀ l\)

\(βˆ€ \varepsilon {\gt}0, βˆƒ 𝛿 {\gt}0, βˆ€ x, |x-x_ 0|{\lt}𝛿, x{\lt} x_ 0, x∈ Iβ‡’f(x){\gt}l-\varepsilon \)

\(βˆ€ \varepsilon {\gt}0, βˆ€ 𝛿 {\gt}0, βˆƒ x, |x-x_ 0|{\lt}𝛿, x{\lt} x_ 0, x∈ I, f(x){\lt}l+\varepsilon \)

In the case \(x_ 0βˆˆβ„\) and \(l=±∞\):

\(\limsup _{xβ†’ x_ 0} f(x) =∞\)

\(βˆ€ z, βˆ€ 𝛿 {\gt}0, βˆƒ x, |x-x_ 0|{\lt}𝛿, xβ‰  x_ 0, x∈ I, f(x){\gt}z \)

\(\limsup _{xβ†’ x_ 0^+} f(x) =∞\)

\(βˆ€ z, βˆ€ 𝛿 {\gt}0, βˆƒ x, |x-x_ 0|{\lt}𝛿, x{\gt} x_ 0, x∈ I, f(x){\gt}z \)

\(\limsup _{xβ†’ x_ 0^-} f(x) =∞\)

\(βˆ€ z, βˆ€ 𝛿 {\gt}0, βˆƒ x, |x-x_ 0|{\lt}𝛿, x{\lt} x_ 0, x∈ I, f(x){\gt}z \)

\(\limsup _{xβ†’ x_ 0} f(x) =-∞\)

\(βˆ€ z, βˆƒ 𝛿 {\gt}0, βˆ€ x, |x-x_ 0|{\lt}𝛿, xβ‰  x_ 0, x∈ Iβ‡’f(x){\lt}z \)

\(\limsup _{xβ†’ x_ 0^+} f(x) =-∞\)

\(βˆ€ z, βˆƒ 𝛿 {\gt}0, βˆ€ x, |x-x_ 0|{\lt}𝛿, x{\gt} x_ 0, x∈ Iβ‡’f(x){\lt}z \)

\(\limsup _{xβ†’ x_ 0^-} f(x) =-∞\)

\(βˆ€ z, βˆƒ 𝛿 {\gt}0, βˆ€ x, |x-x_ 0|{\lt}𝛿, x{\lt} x_ 0, x∈ Iβ‡’f(x){\lt}z \)

\(\liminf _{xβ†’ x_ 0} f(x) =∞\)

\(βˆ€ z, βˆƒ 𝛿 {\gt}0, βˆ€ x, |x-x_ 0|{\lt}𝛿, xβ‰  x_ 0, x∈ Iβ‡’f(x){\gt}z \)

\(\liminf _{xβ†’ x_ 0^+} f(x) =∞\)

\(βˆ€ z, βˆƒ 𝛿 {\gt}0, βˆ€ x, |x-x_ 0|{\lt}𝛿, x{\gt} x_ 0, x∈ Iβ‡’f(x){\gt}z \)

\(\liminf _{xβ†’ x_ 0^-} f(x) =∞\)

\(βˆ€ z, βˆƒ 𝛿 {\gt}0, βˆ€ x, |x-x_ 0|{\lt}𝛿, x{\lt} x_ 0, x∈ Iβ‡’f(x){\gt}z \)

\(\liminf _{xβ†’ x_ 0} f(x) =-∞\)

\(βˆ€ z, βˆ€ 𝛿 {\gt}0, βˆƒ x, |x-x_ 0|{\lt}𝛿, xβ‰  x_ 0, x∈ I, f(x){\lt}z \)

\(\liminf _{xβ†’ x_ 0^+} f(x) =-∞\)

\(βˆ€ z, βˆ€ 𝛿 {\gt}0, βˆƒ x, |x-x_ 0|{\lt}𝛿, x{\gt} x_ 0, x∈ I, f(x){\lt}z \)

\(\liminf _{xβ†’ x_ 0^-} f(x) =-∞\)

\(βˆ€ z, βˆ€ 𝛿 {\gt}0, βˆƒ x, |x-x_ 0|{\lt}𝛿, x{\lt} x_ 0, x∈ I, f(x){\lt}z \)

In the case \(x_ 0=±∞\) and \(l=±∞\):

\(\limsup _{xβ†’ ∞} f(x) =∞\)

\(βˆ€ z, βˆ€ y,βˆƒ x,x{\gt}y, x∈ I, f(x){\gt}z \)

\(\limsup _{xβ†’ -∞} f(x) =∞\)

\(βˆ€ z, βˆ€ y,βˆƒ x,x{\lt}y, x∈ I, f(x){\gt}z \)

\(\limsup _{xβ†’ ∞} f(x) =-∞\)

\(βˆ€ z, βˆƒ y,βˆ€ x,x{\gt}y, x∈ Iβ‡’f(x){\lt}z \)

\(\limsup _{xβ†’ -∞} f(x) =-∞\)

\(βˆ€ z, βˆƒ y,βˆ€ x,x{\lt}y, x∈ Iβ‡’f(x){\lt}z \)

\(\liminf _{xβ†’ ∞} f(x) =∞\)

\(βˆ€ z, βˆƒ y,βˆ€ x,x{\gt}y, x∈ Iβ‡’f(x){\gt}z \)

\(\liminf _{xβ†’ -∞} f(x) =∞\)

\(βˆ€ z, βˆƒ y,βˆ€ x,x{\lt}y, x∈ Iβ‡’f(x){\gt}z \)

\(\liminf _{xβ†’ ∞} f(x) =-∞\)

\(βˆ€ z, βˆ€ y,βˆƒ x,x{\gt}y, x∈ I, f(x){\lt}z \)

\(\liminf _{xβ†’ -∞} f(x) =-∞\)

\(βˆ€ z, βˆ€ y,βˆƒ x,x{\lt}y, x∈ I, f(x){\lt}z \)

In the case \(x_ 0=±∞\) and \(lβˆˆβ„\):

\(\limsup _{xβ†’ ∞} f(x) ≀ l\)

\(\limsup _{xβ†’ ∞} f(x) β‰₯ l\)

\(βˆ€ \varepsilon {\gt}0, βˆƒ y, βˆ€ x, x{\gt}y, x∈ Iβ‡’f(x){\lt}l+\varepsilon \)

\(βˆ€ \varepsilon {\gt}0, βˆ€ y, βˆƒ x, x{\gt}y, x∈ I, f(x){\gt}l-\varepsilon \)

\(\limsup _{xβ†’ -∞} f(x) ≀ l\)

\(\limsup _{xβ†’ -∞} f(x) β‰₯ l\)

\(βˆ€ \varepsilon {\gt}0, βˆƒ y, βˆ€ x, x{\lt}y, x∈ Iβ‡’f(x){\lt}l+\varepsilon \)

\(βˆ€ \varepsilon {\gt}0, βˆ€ y, βˆƒ x, x{\lt}y, x∈ I, f(x){\gt}l-\varepsilon \)

\(\liminf _{xβ†’ ∞} f(x) ≀ l\)

\(\liminf _{xβ†’ ∞} f(x) β‰₯ l\)

\(βˆ€ \varepsilon {\gt}0, βˆ€ y, βˆƒ x, x{\gt}y, x∈ I, f(x){\lt}l+\varepsilon \)

\(βˆ€ \varepsilon {\gt}0, βˆƒ y, βˆ€ x, x{\gt}y, x∈ Iβ‡’f(x){\gt}l-\varepsilon \)

\(\liminf _{xβ†’ -∞} f(x) ≀ l\)

\(\liminf _{xβ†’ -∞} f(x) β‰₯ l\)

\(βˆ€ \varepsilon {\gt}0, βˆ€ y, βˆƒ x, x{\lt}y, x∈ I, f(x){\lt}l+\varepsilon \)

\(βˆ€ \varepsilon {\gt}0, βˆƒ y, βˆ€ x, x{\lt}y, x∈ Iβ‡’f(x){\gt}l-\varepsilon \)

  1. In the following tables all commas ”,” after the last quantifier should be interpreted as conjunctions ”\(∧\)”, but were written as ”,” for lighten the notation.
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