Metamath Proof Explorer


Theorem constrlccl

Description: Constructible numbers are closed under line-circle intersections. (Contributed by Thierry Arnoux, 2-Nov-2025)

Ref Expression
Hypotheses constrlccl.a φ A Constr
constrlccl.b φ B Constr
constrlccl.c φ G Constr
constrlccl.e φ E Constr
constrlccl.f φ F Constr
constrlccl.t φ T
constrlccl.x φ X
constrlccl.1 φ X = A + T B A
constrlccl.2 φ X G = E F
Assertion constrlccl φ X Constr

Proof

Step Hyp Ref Expression
1 constrlccl.a φ A Constr
2 constrlccl.b φ B Constr
3 constrlccl.c φ G Constr
4 constrlccl.e φ E Constr
5 constrlccl.f φ F Constr
6 constrlccl.t φ T
7 constrlccl.x φ X
8 constrlccl.1 φ X = A + T B A
9 constrlccl.2 φ X G = E F
10 constrcbvlem rec z V y | i z j z k z l z o p y = i + o j i y = k + p l k j i l k 0 i z j z k z m z q z o y = i + o j i y k = m q i z j z k z l z m z q z i l y i = j k y l = m q 0 1 = rec s V x | a s b s c s d s t r x = a + t b a x = c + r d c b a d c 0 a s b s c s e s f s t x = a + t b a x c = e f a s b s c s d s e s f s a d x a = b c x d = e f 0 1
11 10 1 2 3 4 5 6 7 8 9 constrlccllem φ X Constr