| Metamath Proof Explorer |
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Related theorems GIF version |
| Description: Introduce a consequent to both sides of a logical equivalence. |
| Ref | Expression |
|---|---|
| bi.a | ⊢ (φ ↔ ψ) |
| Ref | Expression |
|---|---|
| imbi1i | ⊢ ((φ → χ) ↔ (ψ → χ)) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | bi.a | . . . 4 ⊢ (φ ↔ ψ) | |
| 2 | 1 | biimpr 134 | . . 3 ⊢ (ψ → φ) |
| 3 | 2 | syl4 19 | . 2 ⊢ ((φ → χ) → (ψ → χ)) |
| 4 | 1 | biimp 133 | . . 3 ⊢ (φ → ψ) |
| 5 | 4 | syl4 19 | . 2 ⊢ ((ψ → χ) → (φ → χ)) |
| 6 | 3, 5 | impbi 139 | 1 ⊢ ((φ → χ) ↔ (ψ → χ)) |
| Colors of variables: wff set class |
| Syntax hints: → wi 2 ↔ wb 127 |
| This theorem is referenced by: imbi12i 163 imor 204 impexp 276 bibi2i 460 19.37 759 sbor 887 sb19.21 888 mo4f 1028 axun 1081 axpow 1082 r3al 1240 r19.23v 1282 ralcom 1312 reu2 1338 reu4 1340 unss 1632 inssdif0 1754 pwex 1806 snss 1849 unissb 1941 uniex 1947 intun 1989 intpr 1990 dfiin2 2015 iunss 2017 dftr2 2043 dfom2 2374 reluni 2493 dffun2 2674 dffun4 2676 dffun5 2677 dffun6 2687 fununi 2705 funcnvuni 2706 f1fv 2916 setind2 3493 ranksn 3532 scottexs 3543 scott0s 3544 kardex 3550 karden 3551 kmlem11 3590 axpowndlem3 3745 zfcndun 3761 zfcndpow 3762 zfcndac 3765 suppsr3 4018 nnwos 4610 zmin 4617 choc0 5291 h1deot 5454 h1det 5455 |
| This theorem was proved from axioms: ax-1 3 ax-2 4 ax-3 5 ax-mp 6 |
| This theorem depends on definitions: df-bi 128 |