Metamath Proof Explorer
Description: From these two negated implications it is not the case their nonnegated
forms are both true. (Contributed by Jarvin Udandy, 11-Sep-2020)
|
|
Ref |
Expression |
|
Hypotheses |
twonotinotbothi.1 |
⊢ ¬ ( 𝜑 → 𝜓 ) |
|
|
twonotinotbothi.2 |
⊢ ¬ ( 𝜒 → 𝜃 ) |
|
Assertion |
twonotinotbothi |
⊢ ¬ ( ( 𝜑 → 𝜓 ) ∧ ( 𝜒 → 𝜃 ) ) |
Proof
Step |
Hyp |
Ref |
Expression |
1 |
|
twonotinotbothi.1 |
⊢ ¬ ( 𝜑 → 𝜓 ) |
2 |
|
twonotinotbothi.2 |
⊢ ¬ ( 𝜒 → 𝜃 ) |
3 |
1
|
orci |
⊢ ( ¬ ( 𝜑 → 𝜓 ) ∨ ¬ ( 𝜒 → 𝜃 ) ) |
4 |
|
pm3.14 |
⊢ ( ( ¬ ( 𝜑 → 𝜓 ) ∨ ¬ ( 𝜒 → 𝜃 ) ) → ¬ ( ( 𝜑 → 𝜓 ) ∧ ( 𝜒 → 𝜃 ) ) ) |
5 |
3 4
|
ax-mp |
⊢ ¬ ( ( 𝜑 → 𝜓 ) ∧ ( 𝜒 → 𝜃 ) ) |