Description: Ordered pair membership in the class of complex numbers. (Contributed by NM, 14-May-1996) (New usage is discouraged.)
Ref | Expression | ||
---|---|---|---|
Assertion | opelcn | ⊢ ( 〈 𝐴 , 𝐵 〉 ∈ ℂ ↔ ( 𝐴 ∈ R ∧ 𝐵 ∈ R ) ) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | df-c | ⊢ ℂ = ( R × R ) | |
2 | 1 | eleq2i | ⊢ ( 〈 𝐴 , 𝐵 〉 ∈ ℂ ↔ 〈 𝐴 , 𝐵 〉 ∈ ( R × R ) ) |
3 | opelxp | ⊢ ( 〈 𝐴 , 𝐵 〉 ∈ ( R × R ) ↔ ( 𝐴 ∈ R ∧ 𝐵 ∈ R ) ) | |
4 | 2 3 | bitri | ⊢ ( 〈 𝐴 , 𝐵 〉 ∈ ℂ ↔ ( 𝐴 ∈ R ∧ 𝐵 ∈ R ) ) |