Description: subcl without ax-mulcom . (Contributed by SN, 5-May-2024)
Ref | Expression | ||
---|---|---|---|
Assertion | sn-subcl | ⊢ ( ( 𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ ) → ( 𝐴 − 𝐵 ) ∈ ℂ ) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | subval | ⊢ ( ( 𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ ) → ( 𝐴 − 𝐵 ) = ( ℩ 𝑥 ∈ ℂ ( 𝐵 + 𝑥 ) = 𝐴 ) ) | |
2 | sn-subeu | ⊢ ( ( 𝐵 ∈ ℂ ∧ 𝐴 ∈ ℂ ) → ∃! 𝑥 ∈ ℂ ( 𝐵 + 𝑥 ) = 𝐴 ) | |
3 | 2 | ancoms | ⊢ ( ( 𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ ) → ∃! 𝑥 ∈ ℂ ( 𝐵 + 𝑥 ) = 𝐴 ) |
4 | riotacl | ⊢ ( ∃! 𝑥 ∈ ℂ ( 𝐵 + 𝑥 ) = 𝐴 → ( ℩ 𝑥 ∈ ℂ ( 𝐵 + 𝑥 ) = 𝐴 ) ∈ ℂ ) | |
5 | 3 4 | syl | ⊢ ( ( 𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ ) → ( ℩ 𝑥 ∈ ℂ ( 𝐵 + 𝑥 ) = 𝐴 ) ∈ ℂ ) |
6 | 1 5 | eqeltrd | ⊢ ( ( 𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ ) → ( 𝐴 − 𝐵 ) ∈ ℂ ) |