Metamath Proof Explorer


Theorem astbstanbst

Description: Given a is equivalent to T., also given that b is equivalent to T, there exists a proof for a and b is equivalent to T. (Contributed by Jarvin Udandy, 29-Aug-2016)

Ref Expression
Hypotheses astbstanbst.1 ( 𝜑 ↔ ⊤ )
astbstanbst.2 ( 𝜓 ↔ ⊤ )
Assertion astbstanbst ( ( 𝜑𝜓 ) ↔ ⊤ )

Proof

Step Hyp Ref Expression
1 astbstanbst.1 ( 𝜑 ↔ ⊤ )
2 astbstanbst.2 ( 𝜓 ↔ ⊤ )
3 1 aistia 𝜑
4 2 aistia 𝜓
5 3 4 pm3.2i ( 𝜑𝜓 )
6 5 bitru ( ( 𝜑𝜓 ) ↔ ⊤ )