Metamath Proof Explorer


Theorem redivrec2d

Description: Relationship between division and reciprocal. (Contributed by SN, 9-Apr-2026)

Ref Expression
Hypotheses redivrec2d.a φ A
redivrec2d.b φ B
redivrec2d.z φ B 0
Assertion redivrec2d φ A / B = 1 / B A

Proof

Step Hyp Ref Expression
1 redivrec2d.a φ A
2 redivrec2d.b φ B
3 redivrec2d.z φ B 0
4 2 3 rerecidd φ B 1 / B = 1
5 4 oveq1d φ B 1 / B A = 1 A
6 2 recnd φ B
7 2 3 sn-rereccld φ 1 / B
8 7 recnd φ 1 / B
9 1 recnd φ A
10 6 8 9 mulassd φ B 1 / B A = B 1 / B A
11 remullid A 1 A = A
12 1 11 syl φ 1 A = A
13 5 10 12 3eqtr3d φ B 1 / B A = A
14 7 1 remulcld φ 1 / B A
15 1 14 2 3 redivmuld φ A / B = 1 / B A B 1 / B A = A
16 13 15 mpbird φ A / B = 1 / B A