Nuprl Lemma : qmul-qdiv-cancel

∀[a,b:ℚ].  (a * (b/a)) = b ∈ ℚ supposing ¬(a = 0 ∈ ℚ)


Proof




Definitions occuring in Statement :  qdiv: (r/s),  qmul: r * s,  rationals: ℚ,  uimplies: b supposing a,  uall: ∀[x:A]. B[x],  not: ¬A,  natural_number: $n,  equal: s = t ∈ T
Definitions unfolded in proof :  uall: ∀[x:A]. B[x],  member: t ∈ T,  uimplies: b supposing a,  not: ¬A,  subtype_rel: A ⊆r B,  uiff: uiff(P;Q),  and: P ∧ Q,  prop: ℙ,  qdiv: (r/s),  true: True,  squash: ↓T,  guard: {T},  iff: P ⇐⇒ Q,  rev_implies: P ⇐ Q,  implies: P ⇒ Q
Lemmas referenced :  assert-qeq,  int-subtype-rationals,  assert_wf,  qeq_wf2,  not_wf,  equal-wf-T-base,  rationals_wf,  qinv_wf,  equal_wf,  qmul_assoc,  iff_weakening_equal,  qmul_inv_l,  qmul_wf,  squash_wf,  true_wf,  qmul_comm_qrng,  qmul_ac_1_qrng,  qmul_one_qrng
Rules used in proof :  sqequalSubstitution,  sqequalTransitivity,  computationStep,  sqequalReflexivity,  isect_memberFormation,  introduction,  cut,  hypothesis,  addLevel,  sqequalHypSubstitution,  impliesFunctionality,  extract_by_obid,  isectElimination,  thin,  hypothesisEquality,  natural_numberEquality,  applyEquality,  sqequalRule,  productElimination,  independent_isectElimination,  because_Cache,  baseClosed,  isect_memberEquality,  axiomEquality,  equalityTransitivity,  equalitySymmetry,  lambdaEquality,  imageElimination,  imageMemberEquality,  independent_functionElimination,  hyp_replacement,  applyLambdaEquality,  universeEquality

Latex:
\mforall{}[a,b:\mBbbQ{}].    (a  *  (b/a))  =  b  supposing  \mneg{}(a  =  0)



Date html generated: 2018_05_21-PM-11_50_48
Last ObjectModification: 2017_07_26-PM-06_44_09

Theory : rationals


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