Database
SUPPLEMENTARY MATERIAL (USERS' MATHBOXES)
Mathbox for Andrew Salmon
Geometry
df-ptdf
Metamath Proof Explorer
Description: Define the predicate PtDf , which is a utility definition used to
shorten definitions and simplify proofs. (Contributed by Andrew Salmon , 15-Jul-2012)
Ref
Expression
Assertion
df-ptdf
⊢ PtDf A B = x ∈ ℝ ⟼ x ⋅ v B - r A + v A 1 2 3
Detailed syntax breakdown
Step
Hyp
Ref
Expression
0
cA
class A
1
cB
class B
2
0 1
cptdfc
class PtDf A B
3
vx
setvar x
4
cr
class ℝ
5
3
cv
setvar x
6
ctimesr
class ⋅ v
7
cminusr
class - r
8
1 0 7
co
class B - r A
9
5 8 6
co
class x ⋅ v B - r A
10
cpv
class + v
11
9 0 10
co
class x ⋅ v B - r A + v A
12
c1
class 1
13
c2
class 2
14
c3
class 3
15
12 13 14
ctp
class 1 2 3
16
11 15
cima
class x ⋅ v B - r A + v A 1 2 3
17
3 4 16
cmpt
class x ∈ ℝ ⟼ x ⋅ v B - r A + v A 1 2 3
18
2 17
wceq
wff PtDf A B = x ∈ ℝ ⟼ x ⋅ v B - r A + v A 1 2 3