Metamath Proof Explorer
Description: Constructor rule for -/\ . (Contributed by Anthony Hart, 2-Sep-2011)
|
|
Ref |
Expression |
|
Hypotheses |
nabi12i.1 |
|- ( ph <-> ps ) |
|
|
nabi12i.2 |
|- ( ch <-> th ) |
|
|
nabi12i.3 |
|- ( ps -/\ th ) |
|
Assertion |
nabi12i |
|- ( ph -/\ ch ) |
Proof
Step |
Hyp |
Ref |
Expression |
1 |
|
nabi12i.1 |
|- ( ph <-> ps ) |
2 |
|
nabi12i.2 |
|- ( ch <-> th ) |
3 |
|
nabi12i.3 |
|- ( ps -/\ th ) |
4 |
1 3
|
nabi1i |
|- ( ph -/\ th ) |
5 |
2 4
|
nabi2i |
|- ( ph -/\ ch ) |