Metamath Proof Explorer


Theorem flt4lem1

Description: Satisfy the antecedent used in several pythagtrip lemmas, with A , C coprime rather than A , B . (Contributed by SN, 21-Aug-2024)

Ref Expression
Hypotheses flt4lem1.a φ A
flt4lem1.b φ B
flt4lem1.c φ C
flt4lem1.1 φ ¬ 2 A
flt4lem1.2 φ A gcd C = 1
flt4lem1.3 φ A 2 + B 2 = C 2
Assertion flt4lem1 φ A B C A 2 + B 2 = C 2 A gcd B = 1 ¬ 2 A

Proof

Step Hyp Ref Expression
1 flt4lem1.a φ A
2 flt4lem1.b φ B
3 flt4lem1.c φ C
4 flt4lem1.1 φ ¬ 2 A
5 flt4lem1.2 φ A gcd C = 1
6 flt4lem1.3 φ A 2 + B 2 = C 2
7 1 2 3 3jca φ A B C
8 1 2 3 5 6 fltabcoprm φ A gcd B = 1
9 8 4 jca φ A gcd B = 1 ¬ 2 A
10 7 6 9 3jca φ A B C A 2 + B 2 = C 2 A gcd B = 1 ¬ 2 A