Description: Equality theorem for the directed integral. Deduction form. (Contributed by GG, 1-Sep-2025)
| Ref | Expression | ||
|---|---|---|---|
| Hypotheses | ditgeq12d.1 | ⊢ ( 𝜑 → 𝐴 = 𝐵 ) | |
| ditgeq12d.2 | ⊢ ( 𝜑 → 𝐶 = 𝐷 ) | ||
| Assertion | ditgeq12d | ⊢ ( 𝜑 → ⨜ [ 𝐴 → 𝐶 ] 𝐸 d 𝑥 = ⨜ [ 𝐵 → 𝐷 ] 𝐸 d 𝑥 ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | ditgeq12d.1 | ⊢ ( 𝜑 → 𝐴 = 𝐵 ) | |
| 2 | ditgeq12d.2 | ⊢ ( 𝜑 → 𝐶 = 𝐷 ) | |
| 3 | ditgeq1 | ⊢ ( 𝐴 = 𝐵 → ⨜ [ 𝐴 → 𝐶 ] 𝐸 d 𝑥 = ⨜ [ 𝐵 → 𝐶 ] 𝐸 d 𝑥 ) | |
| 4 | ditgeq2 | ⊢ ( 𝐶 = 𝐷 → ⨜ [ 𝐵 → 𝐶 ] 𝐸 d 𝑥 = ⨜ [ 𝐵 → 𝐷 ] 𝐸 d 𝑥 ) | |
| 5 | 3 4 | sylan9eq | ⊢ ( ( 𝐴 = 𝐵 ∧ 𝐶 = 𝐷 ) → ⨜ [ 𝐴 → 𝐶 ] 𝐸 d 𝑥 = ⨜ [ 𝐵 → 𝐷 ] 𝐸 d 𝑥 ) |
| 6 | 1 2 5 | syl2anc | ⊢ ( 𝜑 → ⨜ [ 𝐴 → 𝐶 ] 𝐸 d 𝑥 = ⨜ [ 𝐵 → 𝐷 ] 𝐸 d 𝑥 ) |