Description: Lemma 1 for fundcmpsurinj . (Contributed by AV, 4-Mar-2024)
| Ref | Expression | ||
|---|---|---|---|
| Hypotheses | fundcmpsurinj.p | ⊢ 𝑃 = { 𝑧 ∣ ∃ 𝑥 ∈ 𝐴 𝑧 = ( ◡ 𝐹 “ { ( 𝐹 ‘ 𝑥 ) } ) } | |
| fundcmpsurinj.g | ⊢ 𝐺 = ( 𝑥 ∈ 𝐴 ↦ ( ◡ 𝐹 “ { ( 𝐹 ‘ 𝑥 ) } ) ) | ||
| Assertion | fundcmpsurinjlem1 | ⊢ ran 𝐺 = 𝑃 | 
| Step | Hyp | Ref | Expression | 
|---|---|---|---|
| 1 | fundcmpsurinj.p | ⊢ 𝑃 = { 𝑧 ∣ ∃ 𝑥 ∈ 𝐴 𝑧 = ( ◡ 𝐹 “ { ( 𝐹 ‘ 𝑥 ) } ) } | |
| 2 | fundcmpsurinj.g | ⊢ 𝐺 = ( 𝑥 ∈ 𝐴 ↦ ( ◡ 𝐹 “ { ( 𝐹 ‘ 𝑥 ) } ) ) | |
| 3 | 2 | rnmpt | ⊢ ran 𝐺 = { 𝑧 ∣ ∃ 𝑥 ∈ 𝐴 𝑧 = ( ◡ 𝐹 “ { ( 𝐹 ‘ 𝑥 ) } ) } | 
| 4 | 3 1 | eqtr4i | ⊢ ran 𝐺 = 𝑃 |