Nuprl Lemma : rabs-rleq

∀x,z:ℝ.  (|x| ≤ z ⇐⇒ (-(z) ≤ x) ∧ (x ≤ z))


Proof




Definitions occuring in Statement :  rleq: x ≤ y,  rabs: |x|,  rminus: -(x),  real: ℝ,  all: ∀x:A. B[x],  iff: P ⇐⇒ Q,  and: P ∧ Q
Definitions unfolded in proof :  uall: ∀[x:A]. B[x],  member: t ∈ T,  top: Top,  all: ∀x:A. B[x],  iff: P ⇐⇒ Q,  and: P ∧ Q,  implies: P ⇒ Q,  uiff: uiff(P;Q),  uimplies: b supposing a,  prop: ℙ,  rev_implies: P ⇐ Q,  rev_uimplies: rev_uimplies(P;Q),  cand: A c∧ B,  req_int_terms: t1 ≡ t2,  false: False,  not: ¬A

Latex:
\mforall{}x,z:\mBbbR{}.    (|x|  \mleq{}  z  \mLeftarrow{}{}\mRightarrow{}  (-(z)  \mleq{}  x)  \mwedge{}  (x  \mleq{}  z))



Date html generated: 2020_05_20-AM-11_02_01
Last ObjectModification: 2019_12_12-AM-10_28_13

Theory : reals


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