Nuprl Lemma : assert-geo-isleft

∀g:OrientedPlane. ∀a,b:Point. ∀c:{c:Point| a # bc} .  (↑isleft(a;b;c) ⇐⇒ a leftof bc)


Proof




Definitions occuring in Statement :  geo-isleft: isleft(a;b;c),  oriented-plane: OrientedPlane,  geo-lsep: a # bc,  geo-left: a leftof bc,  geo-point: Point,  assert: ↑b,  all: ∀x:A. B[x],  iff: P ⇐⇒ Q,  set: {x:A| B[x]} 
Definitions unfolded in proof :  so_apply: x[s],  so_lambda: λ2x.t[x],  guard: {T},  subtype_rel: A ⊆r B,  bfalse: ff,  false: False,  not: ¬A,  uimplies: b supposing a,  true: True,  btrue: tt,  isl: isl(x),  ifthenelse: if b then t else f fi ,  assert: ↑b,  rev_implies: P ⇐ Q,  and: P ∧ Q,  iff: P ⇐⇒ Q,  or: P ∨ Q,  implies: P ⇒ Q,  prop: ℙ,  oriented-plane: Error :oriented-plane,  uall: ∀[x:A]. B[x],  member: t ∈ T,  geo-isleft: isleft(a;b;c),  all: ∀x:A. B[x]
Lemmas referenced :  Error :basic-geo-primitives_wf,  Error :basic-geo-structure_wf,  basic-geometry-_wf,  Error :oriented-plane_wf,  subtype_rel_transitivity,  Error :oriented-plane-subtype,  basic-geometry--subtype,  geo-point_wf,  set_wf,  equal_wf,  btrue_neq_bfalse,  bfalse_wf,  assert_elim,  isl_wf,  assert_wf,  geo-left_wf,  or_wf,  geo-lsep_wf,  geo-orientation_wf,  not-left-and-right
Rules used in proof :  lambdaEquality,  instantiate,  applyEquality,  dependent_functionElimination,  voidElimination,  independent_functionElimination,  equalitySymmetry,  equalityTransitivity,  sqequalRule,  levelHypothesis,  independent_isectElimination,  inrEquality,  addLevel,  natural_numberEquality,  inlEquality,  voidEquality,  independent_pairFormation,  unionElimination,  because_Cache,  dependent_set_memberEquality,  hypothesis,  hypothesisEquality,  rename,  setElimination,  thin,  isectElimination,  sqequalHypSubstitution,  extract_by_obid,  introduction,  cut,  lambdaFormation,  sqequalReflexivity,  computationStep,  sqequalTransitivity,  sqequalSubstitution

Latex:
\mforall{}g:OrientedPlane.  \mforall{}a,b:Point.  \mforall{}c:\{c:Point|  a  \#  bc\}  .    (\muparrow{}isleft(a;b;c)  \mLeftarrow{}{}\mRightarrow{}  a  leftof  bc)



Date html generated: 2017_10_02-PM-06_50_05
Last ObjectModification: 2017_08_06-PM-07_29_51

Theory : euclidean!plane!geometry


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