Nuprl Lemma : mul-non-neg1

∀[x,y:ℤ].  (0 ≤ (x * y)) supposing ((0 ≤ y) and (0 ≤ x))


Proof




Definitions occuring in Statement :  uimplies: b supposing a,  uall: ∀[x:A]. B[x],  le: A ≤ B,  multiply: n * m,  natural_number: $n,  int: ℤ
Definitions unfolded in proof :  uall: ∀[x:A]. B[x],  member: t ∈ T,  uimplies: b supposing a,  nat: ℕ,  prop: ℙ,  le: A ≤ B,  and: P ∧ Q,  not: ¬A,  implies: P ⇒ Q,  false: False
Lemmas referenced :  mul_bounds_1a,  le_wf,  less_than'_wf
Rules used in proof :  sqequalSubstitution,  sqequalTransitivity,  computationStep,  sqequalReflexivity,  isect_memberFormation,  introduction,  cut,  lemma_by_obid,  sqequalHypSubstitution,  isectElimination,  thin,  dependent_set_memberEquality,  hypothesisEquality,  hypothesis,  natural_numberEquality,  because_Cache,  sqequalRule,  productElimination,  independent_pairEquality,  lambdaEquality,  dependent_functionElimination,  multiplyEquality,  axiomEquality,  equalityTransitivity,  equalitySymmetry,  isect_memberEquality,  intEquality,  voidElimination

Latex:
\mforall{}[x,y:\mBbbZ{}].    (0  \mleq{}  (x  *  y))  supposing  ((0  \mleq{}  y)  and  (0  \mleq{}  x))



Date html generated: 2016_05_14-AM-07_20_45
Last ObjectModification: 2015_12_26-PM-01_32_01

Theory : int_2


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