Nuprl Lemma : Euclid-erect-perp-ext
∀e:EuclideanPlane. ∀a:Point. ∀b:{b:Point| a # b} . ∀c:{c:Point| Colinear(a;b;c)} .  (∃p:Point [(ab  ⊥c pc ∧ p # ab)])
Proof
Definitions occuring in Statement : 
geo-perp-in: ab  ⊥x cd, 
euclidean-plane: EuclideanPlane, 
geo-colinear: Colinear(a;b;c), 
geo-lsep: a # bc, 
geo-sep: a # b, 
geo-point: Point, 
all: ∀x:A. B[x], 
sq_exists: ∃x:A [B[x]], 
and: P ∧ Q, 
set: {x:A| B[x]} 
Definitions unfolded in proof : 
member: t ∈ T, 
record-select: r.x, 
ifthenelse: if b then t else f fi , 
Euclid-erect-perp, 
geo-sep-or, 
geo-sep-sym, 
symmetric-point-construction, 
Euclid-Prop1, 
basic-geo-sep-sym, 
sq_stable__geo-axioms, 
Euclid-Prop1-left-ext, 
geo-cong-preserves-gt-prim, 
sq_stable-geo-axioms-if, 
sq_stable__geo-between, 
sq_stable__geo-congruent, 
sq_stable__geo-gt-prim, 
sq_stable__geo-lsep, 
any: any x, 
sq_stable__and, 
sq_stable__all, 
uall: ∀[x:A]. B[x], 
so_lambda: so_lambda4, 
so_apply: x[s1;s2;s3;s4], 
so_lambda: λ2x y.t[x; y], 
so_apply: x[s1;s2], 
uimplies: b supposing a, 
so_lambda: λ2x.t[x], 
so_apply: x[s]
Latex:
\mforall{}e:EuclideanPlane.  \mforall{}a:Point.  \mforall{}b:\{b:Point|  a  \#  b\}  .  \mforall{}c:\{c:Point|  Colinear(a;b;c)\}  .
    (\mexists{}p:Point  [(ab    \mbot{}c  pc  \mwedge{}  p  \#  ab)])
Date html generated:
2020_05_20-AM-10_03_52
Last ObjectModification:
2020_01_27-PM-07_14_43
Theory : euclidean!plane!geometry
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