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Diff — Limit of a function

Revision #1960 → #2382 · back to history

modifiedLimit of 4x+1 at x=20cd8765320cf
FieldFrom #1960To #2382
noteThis is a worked numerical example, not a named theorem; no dedicated Mathlib statement was located.Worked numerical example, not a named theorem; no dedicated Mathlib statement located.
modifiedLimit independent of value at p1e648b21e6f8
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noteMathlib's `𝓝[≠] p` filter encodes the deleted neighborhood used to ignore `f p`, but the article's specific example itself is not formalized.Mathlib's `𝓝[≠] p` filter (built from `nhdsWithin`) encodes the deleted neighborhood used to ignore `f p`, but the article's specific example itself is not formalized.
modifiedWhere limits can existf10056af019e
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noteMathlib uses `(𝓝[s \ {p}] p).NeBot` (cluster-point conditions) for the analogous existence requirement, but the article's exact closure/interior-based statement is not stated as a single lemma.Mathlib uses `(𝓝[s \ {p}] p).NeBot` (cluster-point conditions) for the analogous existence requirement, but the article's exact closure/interior-based statement is not a single named lemma.
modifiedRight-handed limit07fd91316c99
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note`Function.rightLim` and `Tendsto f (𝓝[>] p) (𝓝 L)` (with `nhdsGT` notation in `Mathlib.Topology.Defs.Filter`) capture the right-handed limit.`Function.rightLim` and `Tendsto f (𝓝[>] p) (𝓝 L)` capture the right-handed limit.
modifiedNon-existence implies non-zero oscillationfd8c5641d4a1
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mathlib.decleq_zero_iff_continuousAtOscillation.eq_zero_iff_continuousAt
modifiedLimit as x approaches infinity82337ce98a87
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mathlib.moduleMathlib.Order.Filter.AtTopBot.BasicMathlib.Order.Filter.AtTopBot.Defs
modifiedLimit as x approaches minus infinity52c385f074b6
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mathlib.moduleMathlib.Order.Filter.AtTopBot.BasicMathlib.Order.Filter.AtTopBot.Defs
modifiedLimit at −∞ of exponential decayab1a6d4ec615
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noteSpecific worked example; the general limit `Real.tendsto_exp_atBot` is in Mathlib but this exact computation is not.Specific worked example; the general limit `Real.tendsto_exp_atBot` exists but this exact computation does not.
modifiedDouble (multiple) limit87d451fd6c88
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mathlib.declFilter.prodFilter.instSProd
mathlib.moduleMathlib.Order.Filter.ProdMathlib.Order.Filter.Defs
noteThe double/multiple limit is `Tendsto f (𝓝 p ×ˢ 𝓝 q) (𝓝 L)` using the product `Filter.prod`.The double/multiple limit is `Tendsto f (𝓝 p ×ˢ 𝓝 q) (𝓝 L)`, with the product filter supplied by `Filter.instSProd`.
modifiedDouble limit at +∞e01e24e15cae
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mathlib.declFilter.prodFilter.instSProd
mathlib.moduleMathlib.Order.Filter.ProdMathlib.Order.Filter.Defs
noteExpressed as `Tendsto f (atTop ×ˢ atTop) (𝓝 L)`.Expressed as `Tendsto f (atTop ×ˢ atTop) (𝓝 L)` via the product filter from `Filter.instSProd`.
modifiedDouble limit at −∞01295098304b
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mathlib.declFilter.prodFilter.instSProd
mathlib.moduleMathlib.Order.Filter.ProdMathlib.Order.Filter.Defs
noteExpressed as `Tendsto f (atBot ×ˢ atBot) (𝓝 L)`.Expressed as `Tendsto f (atBot ×ˢ atBot) (𝓝 L)` via the product filter from `Filter.instSProd`.
modifiedLimit of a vector-valued function (Euclidean)208e5734c7dc
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mathlib.moduleMathlib.Analysis.InnerProductSpace.EuclideanDistMathlib.Analysis.InnerProductSpace.PiL2
modifiedLimit under the Manhattan metric0619e3985ff1
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note`PiLp 1 fun i => ℝ` is the Manhattan metric instance; convergence reduces (via `PiLp.equiv`) to the usual product convergence.`PiLp 1 fun i => ℝ` provides the Manhattan (L¹) metric instance; convergence reduces to the usual product convergence.
addedIndeterminate forms212d4ebb9ad4
addedUniqueness of limit in Hausdorff space82f2de18e71f
addedContinuity at limit point characterized by limit3504161dd3e1