Metamath Proof Explorer


Theorem op2nd

Description: Extract the second member of an ordered pair. (Contributed by NM, 5-Oct-2004)

Ref Expression
Hypotheses op1st.1 ⊢ A ∈ V
op1st.2 ⊢ B ∈ V
Assertion op2nd ⊢ 2 nd ⁡ A B = B

Proof

Step Hyp Ref Expression
1 op1st.1 ⊢ A ∈ V
2 op1st.2 ⊢ B ∈ V
3 2ndval ⊢ 2 nd ⁡ A B = ⋃ ran ⁡ A B
4 1 2 op2nda ⊢ ⋃ ran ⁡ A B = B
5 3 4 eqtri ⊢ 2 nd ⁡ A B = B