Nuprl Lemma : rsqrt-rless-iff
∀x,y:{x:ℝ| r0 ≤ x} .  (x < y 
⇐⇒ rsqrt(x) < rsqrt(y))
Proof
Definitions occuring in Statement : 
rsqrt: rsqrt(x)
, 
rleq: x ≤ y
, 
rless: x < y
, 
int-to-real: r(n)
, 
real: ℝ
, 
all: ∀x:A. B[x]
, 
iff: P 
⇐⇒ Q
, 
set: {x:A| B[x]} 
, 
natural_number: $n
Definitions unfolded in proof : 
all: ∀x:A. B[x]
, 
iff: P 
⇐⇒ Q
, 
and: P ∧ Q
, 
implies: P 
⇒ Q
, 
member: t ∈ T
, 
prop: ℙ
, 
uall: ∀[x:A]. B[x]
, 
rev_implies: P 
⇐ Q
, 
subtype_rel: A ⊆r B
, 
so_lambda: λ2x.t[x]
, 
so_apply: x[s]
, 
nat_plus: ℕ+
, 
less_than: a < b
, 
squash: ↓T
, 
less_than': less_than'(a;b)
, 
true: True
, 
nat: ℕ
, 
le: A ≤ B
, 
false: False
, 
not: ¬A
, 
uimplies: b supposing a
Lemmas referenced : 
rsqrt_functionality_wrt_rless, 
rless_wf, 
rsqrt_wf, 
real_wf, 
rleq_wf, 
int-to-real_wf, 
req_wf, 
rmul_wf, 
set_wf, 
rnexp-rless, 
rsqrt_nonneg, 
less_than_wf, 
rless_functionality, 
rnexp_wf, 
false_wf, 
le_wf, 
rsqrt-rnexp-2
Rules used in proof : 
sqequalSubstitution, 
sqequalTransitivity, 
computationStep, 
sqequalReflexivity, 
lambdaFormation, 
independent_pairFormation, 
cut, 
introduction, 
extract_by_obid, 
sqequalHypSubstitution, 
dependent_functionElimination, 
thin, 
hypothesisEquality, 
setElimination, 
rename, 
hypothesis, 
independent_functionElimination, 
isectElimination, 
applyEquality, 
lambdaEquality, 
setEquality, 
productEquality, 
natural_numberEquality, 
sqequalRule, 
because_Cache, 
dependent_set_memberEquality, 
imageMemberEquality, 
baseClosed, 
independent_isectElimination, 
productElimination
Latex:
\mforall{}x,y:\{x:\mBbbR{}|  r0  \mleq{}  x\}  .    (x  <  y  \mLeftarrow{}{}\mRightarrow{}  rsqrt(x)  <  rsqrt(y))
Date html generated:
2018_05_22-PM-02_23_13
Last ObjectModification:
2018_03_27-PM-10_22_47
Theory : reals
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