Nuprl Lemma : sup-angles-preserve-congruence
∀e:HeytingGeometry. ∀a,b,c,x,y,z,a',x':Point.  ((abc ≅a xyz ∧ a # bc ∧ x # yz) ⇒ a-b-a' ⇒ x-y-x' ⇒ a'bc ≅a x'yz)
Proof
Definitions occuring in Statement : 
geo-triangle: a # bc, 
heyting-geometry: HeytingGeometry, 
geo-cong-angle: abc ≅a xyz, 
geo-strict-between: a-b-c, 
geo-point: Point, 
all: ∀x:A. B[x], 
implies: P ⇒ Q, 
and: P ∧ Q
Definitions unfolded in proof : 
heyting-geometry: Error :heyting-geometry, 
true: True, 
prop: ℙ, 
squash: ↓T, 
uiff: uiff(P;Q), 
geo-strict-between: a-b-c, 
uimplies: b supposing a, 
guard: {T}, 
uall: ∀[x:A]. B[x], 
exists: ∃x:A. B[x], 
subtype_rel: A ⊆r B, 
member: t ∈ T, 
and: P ∧ Q, 
implies: P ⇒ Q, 
all: ∀x:A. B[x], 
geo-out: out(p ab), 
geo-cong-tri: Cong3(abc,a'b'c'), 
subtract: n - m, 
cons: [a / b], 
select: L[n], 
less_than: a < b, 
not: ¬A, 
false: False, 
less_than': less_than'(a;b), 
le: A ≤ B, 
lelt: i ≤ j < k, 
int_seg: {i..j-}, 
top: Top, 
l_all: (∀x∈L.P[x]), 
geo-colinear-set: geo-colinear-set(e; L), 
cand: A c∧ B
Lemmas referenced : 
geo-point_wf, 
Error :geo-triangle_wf, 
geo-cong-angle_wf, 
geo-strict-between_wf, 
geo-add-length-comm, 
geo-length-type_wf, 
true_wf, 
squash_wf, 
geo-add-length_wf, 
geo-congruent-iff-length, 
geo-add-length-between, 
geo-between-inner-trans, 
geo-strict-between-sep1, 
geo-between-out, 
geo-out_inversion, 
geo-between-outer-trans, 
geo-strict-between-implies-between, 
geo-between-symmetry, 
geo-bet-out-out-bet, 
Error :basic-geo-primitives_wf, 
Error :basic-geo-structure_wf, 
basic-geometry_wf, 
Error :heyting-geometry_wf, 
subtype_rel_transitivity, 
basic-geometry-subtype, 
geo-strict-between-sep3, 
geo-proper-extend-exists, 
heyting-geometry-subtype, 
cong-angle-out-exists3, 
geo-length-flip, 
geo-sep-sym, 
geo-five-segment, 
lelt_wf, 
false_wf, 
length_of_nil_lemma, 
length_of_cons_lemma, 
geo-triangle-property, 
geo-strict-between-implies-colinear, 
geo-colinear-is-colinear-set, 
geo-triangle-symmetry, 
geo-triangle-colinear, 
cong-angle-out-aux2
Rules used in proof : 
setElimination, 
productEquality, 
baseClosed, 
imageMemberEquality, 
natural_numberEquality, 
equalitySymmetry, 
equalityTransitivity, 
imageElimination, 
lambdaEquality, 
rename, 
independent_isectElimination, 
isectElimination, 
instantiate, 
because_Cache, 
independent_functionElimination, 
sqequalRule, 
hypothesis, 
applyEquality, 
hypothesisEquality, 
dependent_functionElimination, 
extract_by_obid, 
introduction, 
cut, 
thin, 
productElimination, 
sqequalHypSubstitution, 
lambdaFormation, 
sqequalReflexivity, 
computationStep, 
sqequalTransitivity, 
sqequalSubstitution, 
independent_pairFormation, 
dependent_set_memberEquality, 
voidEquality, 
voidElimination, 
isect_memberEquality
Latex:
\mforall{}e:HeytingGeometry.  \mforall{}a,b,c,x,y,z,a',x':Point.
    ((abc  \00D0\msuba{}  xyz  \mwedge{}  a  \#  bc  \mwedge{}  x  \#  yz)  {}\mRightarrow{}  a-b-a'  {}\mRightarrow{}  x-y-x'  {}\mRightarrow{}  a'bc  \00D0\msuba{}  x'yz)
Date html generated:
2017_10_02-PM-07_04_13
Last ObjectModification:
2017_08_08-PM-00_36_16
Theory : euclidean!plane!geometry
Home
Index