Nuprl Lemma : rsqrt-rleq-iff

[x:{x:ℝr0 ≤ x} ]. ∀[c:ℝ].  uiff(rsqrt(x) ≤ c;(r0 ≤ c) ∧ (x ≤ c^2))


Proof




Definitions occuring in Statement :  rsqrt: rsqrt(x) rleq: x ≤ y rnexp: x^k1 int-to-real: r(n) real: uiff: uiff(P;Q) uall: [x:A]. B[x] and: P ∧ Q set: {x:A| B[x]}  natural_number: $n
Definitions unfolded in proof :  uall: [x:A]. B[x] member: t ∈ T uiff: uiff(P;Q) and: P ∧ Q uimplies: supposing a rleq: x ≤ y rnonneg: rnonneg(x) all: x:A. B[x] le: A ≤ B subtype_rel: A ⊆B prop: nat: less_than': less_than'(a;b) not: ¬A implies:  Q false: False rev_uimplies: rev_uimplies(P;Q) rge: x ≥ y guard: {T}
Lemmas referenced :  le_witness_for_triv rleq_wf rsqrt_wf int-to-real_wf rnexp_wf istype-void istype-le real_wf rsqrt_nonneg rleq_functionality_wrt_implies rleq_weakening_equal rnexp_functionality_wrt_rleq rmul_wf rleq_functionality req_weakening rnexp2 rsqrt_squared square-rleq-implies
Rules used in proof :  sqequalSubstitution sqequalTransitivity computationStep sqequalReflexivity isect_memberFormation_alt introduction cut independent_pairFormation sqequalRule sqequalHypSubstitution productElimination thin independent_pairEquality lambdaEquality_alt dependent_functionElimination hypothesisEquality extract_by_obid isectElimination equalityTransitivity hypothesis equalitySymmetry independent_isectElimination functionIsTypeImplies inhabitedIsType universeIsType applyEquality setElimination rename productIsType natural_numberEquality dependent_set_memberEquality_alt lambdaFormation_alt voidElimination isect_memberEquality_alt isectIsTypeImplies setIsType because_Cache independent_functionElimination

Latex:
\mforall{}[x:\{x:\mBbbR{}|  r0  \mleq{}  x\}  ].  \mforall{}[c:\mBbbR{}].    uiff(rsqrt(x)  \mleq{}  c;(r0  \mleq{}  c)  \mwedge{}  (x  \mleq{}  c\^{}2))



Date html generated: 2019_10_30-AM-07_57_15
Last ObjectModification: 2019_06_25-PM-03_53_11

Theory : reals


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