Metamath Proof Explorer


Theorem domnrcan

Description: Right-cancellation law for domains. (Contributed by SN, 21-Jun-2025)

Ref Expression
Hypotheses domnrcan.b ⊢ 𝐵 = ( Base ‘ 𝑅 )
domnrcan.0 ⊢ 0 = ( 0g ‘ 𝑅 )
domnrcan.m ⊢ · = ( .r ‘ 𝑅 )
domnrcan.x ⊢ ( 𝜑 → 𝑋 ∈ 𝐵 )
domnrcan.y ⊢ ( 𝜑 → 𝑌 ∈ 𝐵 )
domnrcan.z ⊢ ( 𝜑 → 𝑍 ∈ ( 𝐵 ∖ { 0 } ) )
domnrcan.r ⊢ ( 𝜑 → 𝑅 ∈ Domn )
domnrcan.1 ⊢ ( 𝜑 → ( 𝑋 · 𝑍 ) = ( 𝑌 · 𝑍 ) )
Assertion domnrcan ( 𝜑 → 𝑋 = 𝑌 )

Proof

Step Hyp Ref Expression
1 domnrcan.b ⊢ 𝐵 = ( Base ‘ 𝑅 )
2 domnrcan.0 ⊢ 0 = ( 0g ‘ 𝑅 )
3 domnrcan.m ⊢ · = ( .r ‘ 𝑅 )
4 domnrcan.x ⊢ ( 𝜑 → 𝑋 ∈ 𝐵 )
5 domnrcan.y ⊢ ( 𝜑 → 𝑌 ∈ 𝐵 )
6 domnrcan.z ⊢ ( 𝜑 → 𝑍 ∈ ( 𝐵 ∖ { 0 } ) )
7 domnrcan.r ⊢ ( 𝜑 → 𝑅 ∈ Domn )
8 domnrcan.1 ⊢ ( 𝜑 → ( 𝑋 · 𝑍 ) = ( 𝑌 · 𝑍 ) )
9 1 2 3 4 5 6 7 domnrcanb ⊢ ( 𝜑 → ( ( 𝑋 · 𝑍 ) = ( 𝑌 · 𝑍 ) ↔ 𝑋 = 𝑌 ) )
10 8 9 mpbid ⊢ ( 𝜑 → 𝑋 = 𝑌 )