Nuprl Lemma : qdiv_functionality_wrt_qless
∀[a,b,c,d:ℚ].  ((a/c) < (b/d)) supposing ((c ≥ d) and a < b and 0 < d and (0 ≤ a))
Proof
Definitions occuring in Statement : 
qge: a ≥ b, 
qle: r ≤ s, 
qless: r < s, 
qdiv: (r/s), 
rationals: 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, 
not: ¬A, 
implies: P ⇒ Q, 
qge: a ≥ b, 
guard: {T}, 
subtype_rel: A ⊆r B, 
false: False, 
prop: ℙ, 
uiff: uiff(P;Q), 
and: P ∧ Q, 
rev_uimplies: rev_uimplies(P;Q), 
squash: ↓T, 
true: True, 
iff: P ⇐⇒ Q, 
rev_implies: P ⇐ Q
Lemmas referenced : 
qle_witness, 
qle_weakening_lt_qorder, 
qless_transitivity_1_qorder, 
qmul_preserves_qle2, 
qmul_ac_1_qrng, 
qmul_comm_qrng, 
iff_weakening_equal, 
qmul_wf, 
qmul-qdiv-cancel, 
true_wf, 
squash_wf, 
qmul_preserves_qless, 
qle_wf, 
qless_wf, 
qge_wf, 
rationals_wf, 
equal_wf, 
qless_irreflexivity, 
qle_weakening_eq_qorder, 
int-subtype-rationals, 
qless_transitivity_2_qorder, 
qdiv_wf, 
qless_witness
Rules used in proof : 
sqequalSubstitution, 
sqequalTransitivity, 
computationStep, 
sqequalReflexivity, 
isect_memberFormation, 
introduction, 
cut, 
lemma_by_obid, 
sqequalHypSubstitution, 
isectElimination, 
thin, 
because_Cache, 
independent_isectElimination, 
lambdaFormation, 
hypothesis, 
natural_numberEquality, 
applyEquality, 
sqequalRule, 
hypothesisEquality, 
voidElimination, 
independent_functionElimination, 
isect_memberEquality, 
equalityTransitivity, 
equalitySymmetry, 
productElimination, 
lambdaEquality, 
imageElimination, 
imageMemberEquality, 
baseClosed, 
universeEquality, 
independent_pairFormation
Latex:
\mforall{}[a,b,c,d:\mBbbQ{}].    ((a/c)  <  (b/d))  supposing  ((c  \mgeq{}  d)  and  a  <  b  and  0  <  d  and  (0  \mleq{}  a))
Date html generated:
2016_05_15-PM-11_04_35
Last ObjectModification:
2016_01_16-PM-09_28_38
Theory : rationals
Home
Index