Metamath Proof Explorer


Theorem orel

Description: An inference for disjunction elimination. (Contributed by Giovanni Mascellani, 24-May-2019)

Ref Expression
Hypotheses orel.1
|- ( ( ps /\ et ) -> th )
orel.2
|- ( ( ch /\ rh ) -> th )
orel.3
|- ( ph -> ( ps \/ ch ) )
Assertion orel
|- ( ( ph /\ ( et /\ rh ) ) -> th )

Proof

Step Hyp Ref Expression
1 orel.1
 |-  ( ( ps /\ et ) -> th )
2 orel.2
 |-  ( ( ch /\ rh ) -> th )
3 orel.3
 |-  ( ph -> ( ps \/ ch ) )
4 simprl
 |-  ( ( ph /\ ( et /\ rh ) ) -> et )
5 1 ancoms
 |-  ( ( et /\ ps ) -> th )
6 4 5 sylan
 |-  ( ( ( ph /\ ( et /\ rh ) ) /\ ps ) -> th )
7 simprr
 |-  ( ( ph /\ ( et /\ rh ) ) -> rh )
8 2 ancoms
 |-  ( ( rh /\ ch ) -> th )
9 7 8 sylan
 |-  ( ( ( ph /\ ( et /\ rh ) ) /\ ch ) -> th )
10 3 adantr
 |-  ( ( ph /\ ( et /\ rh ) ) -> ( ps \/ ch ) )
11 6 9 10 mpjaodan
 |-  ( ( ph /\ ( et /\ rh ) ) -> th )