Nuprl Lemma : geo-add-length-implies-eq-zero

∀[e:BasicGeometry]. ∀[x,y:Length].  y = 0 ∈ Length supposing x = x + y ∈ Length


Proof




Definitions occuring in Statement :  geo-add-length: p + q,  geo-zero-length: 0,  geo-length-type: Length,  basic-geometry: BasicGeometry,  uimplies: b supposing a,  uall: ∀[x:A]. B[x],  equal: s = t ∈ T
Definitions unfolded in proof :  geo-zero-length: 0,  implies: P ⇒ Q,  rev_implies: P ⇐ Q,  and: P ∧ Q,  iff: P ⇐⇒ Q,  guard: {T},  subtype_rel: A ⊆r B,  true: True,  prop: ℙ,  squash: ↓T,  uimplies: b supposing a,  member: t ∈ T,  uall: ∀[x:A]. B[x]
Lemmas referenced :  basic-geometry_wf,  geo-add-length_wf,  geo-zero-length_wf,  geo-add-length-cancel-left,  iff_weakening_equal,  geo-add-length-zero,  geo-length-type_wf,  true_wf,  squash_wf,  equal_wf
Rules used in proof :  because_Cache,  axiomEquality,  isect_memberEquality,  independent_functionElimination,  productElimination,  independent_isectElimination,  baseClosed,  imageMemberEquality,  sqequalRule,  natural_numberEquality,  universeEquality,  equalitySymmetry,  hypothesis,  equalityTransitivity,  hypothesisEquality,  isectElimination,  extract_by_obid,  imageElimination,  sqequalHypSubstitution,  lambdaEquality,  thin,  applyEquality,  cut,  introduction,  isect_memberFormation,  sqequalReflexivity,  computationStep,  sqequalTransitivity,  sqequalSubstitution

Latex:
\mforall{}[e:BasicGeometry].  \mforall{}[x,y:Length].    y  =  0  supposing  x  =  x  +  y



Date html generated: 2017_10_02-PM-06_14_37
Last ObjectModification: 2017_08_05-PM-04_11_16

Theory : euclidean!plane!geometry


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