:: PROJRED1 semantic presentation
theorem Th1: :: PROJRED1:1
theorem Th2: :: PROJRED1:2
theorem Th3: :: PROJRED1:3
for
b1 being
IncProjSp for
b2,
b3 being
LINE of
b1 st
b2 <> b3 holds
ex
b4,
b5 being
POINT of
b1 st
(
b4 on b2 & not
b4 on b3 &
b5 on b3 & not
b5 on b2 )
theorem Th4: :: PROJRED1:4
for
b1 being
IncProjSp for
b2,
b3 being
POINT of
b1 st
b2 <> b3 holds
ex
b4,
b5 being
LINE of
b1 st
(
b2 on b4 & not
b2 on b5 &
b3 on b5 & not
b3 on b4 )
theorem Th5: :: PROJRED1:5
theorem Th6: :: PROJRED1:6
theorem Th7: :: PROJRED1:7
theorem Th8: :: PROJRED1:8
theorem Th9: :: PROJRED1:9
theorem Th10: :: PROJRED1:10
canceled;
theorem Th11: :: PROJRED1:11
canceled;
theorem Th12: :: PROJRED1:12
for
b1 being
IncProjSp for
b2,
b3,
b4,
b5 being
POINT of
b1 for
b6,
b7,
b8,
b9 being
LINE of
b1 st
b2 on b6 &
b2 on b7 &
b6 <> b7 &
b3 on b6 &
b2 <> b3 &
b4 on b7 &
b5 on b7 &
b4 <> b5 &
b3 on b8 &
b4 on b8 &
b3 on b9 &
b5 on b9 holds
b8 <> b9
theorem Th13: :: PROJRED1:13
for
b1 being
IncProjSp for
b2,
b3,
b4 being
POINT of
b1 for
b5 being
LINE of
b1 st
b2,
b3,
b4 on b5 holds
(
b2,
b4,
b3 on b5 &
b3,
b2,
b4 on b5 &
b3,
b4,
b2 on b5 &
b4,
b2,
b3 on b5 &
b4,
b3,
b2 on b5 )
theorem Th14: :: PROJRED1:14
for
b1 being
Desarguesian IncProjSp for
b2,
b3,
b4,
b5,
b6,
b7,
b8,
b9,
b10,
b11 being
POINT of
b1 for
b12,
b13,
b14,
b15,
b16,
b17,
b18,
b19,
b20 being
LINE of
b1 st
b2,
b3,
b4 on b12 &
b2,
b6,
b5 on b13 &
b2,
b8,
b7 on b14 &
b8,
b6,
b11 on b15 &
b8,
b9,
b4 on b16 &
b6,
b10,
b4 on b17 &
b11,
b5,
b7 on b18 &
b3,
b9,
b7 on b19 &
b3,
b10,
b5 on b20 &
b12,
b13,
b14 are_mutually_different &
b2 <> b8 &
b2 <> b3 &
b2 <> b5 &
b6 <> b5 holds
ex
b21 being
LINE of
b1 st
b9,
b10,
b11 on b21
Lemma9:
for b1 being IncProjSp
for b2, b3, b4, b5 being POINT of b1
for b6, b7 being LINE of b1 st ex b8 being POINT of b1 st
( b8 on b6 & b8 on b7 ) & b2 on b6 & b3 on b6 & b4 on b6 & b5 on b6 & b2,b3,b4,b5 are_mutually_different holds
ex b8, b9, b10, b11 being POINT of b1 st
( b8 on b7 & b9 on b7 & b10 on b7 & b11 on b7 & b8,b9,b10,b11 are_mutually_different )
theorem Th15: :: PROJRED1:15
for
b1 being
IncProjSp st ex
b2 being
LINE of
b1ex
b3,
b4,
b5,
b6 being
POINT of
b1 st
(
b3 on b2 &
b4 on b2 &
b5 on b2 &
b6 on b2 &
b3,
b4,
b5,
b6 are_mutually_different ) holds
for
b2 being
LINE of
b1 ex
b3,
b4,
b5,
b6 being
POINT of
b1 st
(
b3 on b2 &
b4 on b2 &
b5 on b2 &
b6 on b2 &
b3,
b4,
b5,
b6 are_mutually_different )
Lemma11:
for b1 being Fanoian IncProjSp ex b2, b3, b4, b5, b6, b7, b8 being POINT of b1ex b9, b10, b11, b12, b13, b14, b15, b16 being LINE of b1ex b17 being POINT of b1 st
( not b3 on b13 & not b4 on b13 & not b2 on b12 & not b5 on b12 & not b2 on b14 & not b4 on b14 & not b3 on b15 & not b5 on b15 & b6,b2,b5 on b13 & b6,b3,b4 on b12 & b7,b3,b5 on b14 & b7,b2,b4 on b15 & b8,b2,b3 on b9 & b8,b4,b5 on b10 & b6,b7 on b11 & not b8 on b11 & b7 on b16 & b8 on b16 & b11,b16,b14,b15 are_mutually_different & b17 on b9 & b8,b17,b2,b3 are_mutually_different )
theorem Th16: :: PROJRED1:16
for
b1 being
Fanoian IncProjSp ex
b2,
b3,
b4,
b5,
b6,
b7,
b8 being
POINT of
b1ex
b9,
b10,
b11,
b12,
b13,
b14,
b15,
b16 being
LINE of
b1 st
( not
b3 on b13 & not
b4 on b13 & not
b2 on b12 & not
b5 on b12 & not
b2 on b14 & not
b4 on b14 & not
b3 on b15 & not
b5 on b15 &
b6,
b2,
b5 on b13 &
b6,
b3,
b4 on b12 &
b7,
b3,
b5 on b14 &
b7,
b2,
b4 on b15 &
b8,
b2,
b3 on b9 &
b8,
b4,
b5 on b10 &
b6,
b7 on b11 & not
b8 on b11 )
theorem Th17: :: PROJRED1:17
theorem Th18: :: PROJRED1:18
theorem Th19: :: PROJRED1:19
definition
let c1 be
2-dimensional Desarguesian IncProjSp;
let c2,
c3 be
LINE of
c1;
let c4 be
POINT of
c1;
assume E13:
( not
c4 on c2 & not
c4 on c3 )
;
func IncProj c2,
c4,
c3 -> PartFunc of the
Points of
a1,the
Points of
a1 means :
Def1:
:: PROJRED1:def 1
(
dom a5 c= the
Points of
a1 & ( for
b1 being
POINT of
a1 holds
(
b1 in dom a5 iff
b1 on a2 ) ) & ( for
b1,
b2 being
POINT of
a1 st
b1 on a2 &
b2 on a3 holds
(
a5 . b1 = b2 iff ex
b3 being
LINE of
a1 st
(
a4 on b3 &
b1 on b3 &
b2 on b3 ) ) ) );
existence
ex b1 being PartFunc of the Points of c1,the Points of c1 st
( dom b1 c= the Points of c1 & ( for b2 being POINT of c1 holds
( b2 in dom b1 iff b2 on c2 ) ) & ( for b2, b3 being POINT of c1 st b2 on c2 & b3 on c3 holds
( b1 . b2 = b3 iff ex b4 being LINE of c1 st
( c4 on b4 & b2 on b4 & b3 on b4 ) ) ) )
uniqueness
for b1, b2 being PartFunc of the Points of c1,the Points of c1 st dom b1 c= the Points of c1 & ( for b3 being POINT of c1 holds
( b3 in dom b1 iff b3 on c2 ) ) & ( for b3, b4 being POINT of c1 st b3 on c2 & b4 on c3 holds
( b1 . b3 = b4 iff ex b5 being LINE of c1 st
( c4 on b5 & b3 on b5 & b4 on b5 ) ) ) & dom b2 c= the Points of c1 & ( for b3 being POINT of c1 holds
( b3 in dom b2 iff b3 on c2 ) ) & ( for b3, b4 being POINT of c1 st b3 on c2 & b4 on c3 holds
( b2 . b3 = b4 iff ex b5 being LINE of c1 st
( c4 on b5 & b3 on b5 & b4 on b5 ) ) ) holds
b1 = b2
end;
:: deftheorem Def1 defines IncProj PROJRED1:def 1 :
theorem Th20: :: PROJRED1:20
canceled;
theorem Th21: :: PROJRED1:21
theorem Th22: :: PROJRED1:22
theorem Th23: :: PROJRED1:23
theorem Th24: :: PROJRED1:24
theorem Th25: :: PROJRED1:25
for
b1 being
2-dimensional Desarguesian IncProjSp for
b2,
b3 being
POINT of
b1 for
b4,
b5,
b6 being
LINE of
b1 st not
b2 on b4 & not
b2 on b5 & not
b3 on b5 & not
b3 on b6 holds
(
dom ((IncProj b5,b3,b6) * (IncProj b4,b2,b5)) = dom (IncProj b4,b2,b5) &
rng ((IncProj b5,b3,b6) * (IncProj b4,b2,b5)) = rng (IncProj b5,b3,b6) )
theorem Th26: :: PROJRED1:26
theorem Th27: :: PROJRED1:27
theorem Th28: :: PROJRED1:28
for
b1 being
2-dimensional Desarguesian IncProjSp for
b2,
b3,
b4 being
POINT of
b1 for
b5,
b6,
b7 being
LINE of
b1 st not
b2 on b5 & not
b2 on b6 & not
b3 on b6 & not
b3 on b7 &
b4 on b5 &
b4 on b6 &
b4 on b7 &
b5 <> b7 holds
ex
b8 being
POINT of
b1 st
( not
b8 on b5 & not
b8 on b7 &
(IncProj b6,b3,b7) * (IncProj b5,b2,b6) = IncProj b5,
b8,
b7 )