Nuprl Lemma : qmul_reverses_qle2
∀[a,b,c:ℚ].  uiff(a ≤ b;(b * c) ≤ (a * c)) supposing c < 0
Proof
Definitions occuring in Statement : 
qle: r ≤ s, 
qless: r < s, 
qmul: r * s, 
rationals: ℚ, 
uiff: uiff(P;Q), 
uimplies: b supposing a, 
uall: ∀[x:A]. B[x], 
natural_number: $n
Definitions unfolded in proof : 
uall: ∀[x:A]. B[x], 
member: t ∈ T, 
uimplies: b supposing a, 
uiff: uiff(P;Q), 
and: P ∧ Q, 
implies: P ⇒ Q, 
prop: ℙ, 
subtype_rel: A ⊆r B, 
true: True, 
squash: ↓T, 
guard: {T}, 
iff: P ⇐⇒ Q, 
rev_implies: P ⇐ Q
Lemmas referenced : 
iff_weakening_equal, 
qmul_com, 
true_wf, 
squash_wf, 
rationals_wf, 
int-subtype-rationals, 
qless_wf, 
qle_wf, 
qmul_wf, 
qle_witness, 
qmul_reverses_qle
Rules used in proof : 
cut, 
lemma_by_obid, 
sqequalHypSubstitution, 
sqequalSubstitution, 
sqequalTransitivity, 
computationStep, 
sqequalReflexivity, 
isectElimination, 
thin, 
hypothesisEquality, 
independent_isectElimination, 
hypothesis, 
productElimination, 
independent_pairFormation, 
isect_memberFormation, 
introduction, 
independent_functionElimination, 
because_Cache, 
natural_numberEquality, 
applyEquality, 
sqequalRule, 
independent_pairEquality, 
isect_memberEquality, 
equalityTransitivity, 
equalitySymmetry, 
lambdaEquality, 
imageElimination, 
imageMemberEquality, 
baseClosed, 
universeEquality
Latex:
\mforall{}[a,b,c:\mBbbQ{}].    uiff(a  \mleq{}  b;(b  *  c)  \mleq{}  (a  *  c))  supposing  c  <  0
Date html generated:
2016_05_15-PM-10_59_46
Last ObjectModification:
2016_01_16-PM-09_31_44
Theory : rationals
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