Nuprl Lemma : rexp-approx-for-small-ext
∀N:ℕ+. ∀x:{x:ℝ| |x| ≤ (r1/r(4))} .  (∃z:ℤ [(|e^x - (r(z)/r(2 * N))| ≤ (r(2)/r(N)))])
Proof
Definitions occuring in Statement : 
rexp: e^x
, 
rdiv: (x/y)
, 
rleq: x ≤ y
, 
rabs: |x|
, 
rsub: x - y
, 
int-to-real: r(n)
, 
real: ℝ
, 
nat_plus: ℕ+
, 
all: ∀x:A. B[x]
, 
sq_exists: ∃x:A [B[x]]
, 
set: {x:A| B[x]} 
, 
multiply: n * m
, 
natural_number: $n
, 
int: ℤ
Definitions unfolded in proof : 
member: t ∈ T
, 
rexp-approx-for-small, 
rexp-approx-lemma-ext
Lemmas referenced : 
rexp-approx-for-small, 
rexp-approx-lemma-ext
Rules used in proof : 
introduction, 
sqequalSubstitution, 
sqequalTransitivity, 
computationStep, 
sqequalReflexivity, 
cut, 
instantiate, 
extract_by_obid, 
hypothesis, 
sqequalRule, 
thin, 
sqequalHypSubstitution, 
equalityTransitivity, 
equalitySymmetry
Latex:
\mforall{}N:\mBbbN{}\msupplus{}.  \mforall{}x:\{x:\mBbbR{}|  |x|  \mleq{}  (r1/r(4))\}  .    (\mexists{}z:\mBbbZ{}  [(|e\^{}x  -  (r(z)/r(2  *  N))|  \mleq{}  (r(2)/r(N)))])
Date html generated:
2019_10_30-AM-11_40_58
Last ObjectModification:
2019_02_08-PM-02_09_33
Theory : reals_2
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