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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