Theorem imass2 5041

Description: Subset theorem for image. Exercise 22(a) of [Enderton] p. 53. (Contributed by NM, 22-Mar-1998.)

Assertion

Ref	Expression
imass2	⊢ (𝐴 ⊆ 𝐵 → (𝐶 “ 𝐴) ⊆ (𝐶 “ 𝐵))

Proof of Theorem imass2

Step	Hyp	Ref	Expression
1		ssres2 4969	. . 3 ⊢ (𝐴 ⊆ 𝐵 → (𝐶 ↾ 𝐴) ⊆ (𝐶 ↾ 𝐵))
2		rnss 4892	. . 3 ⊢ ((𝐶 ↾ 𝐴) ⊆ (𝐶 ↾ 𝐵) → ran (𝐶 ↾ 𝐴) ⊆ ran (𝐶 ↾ 𝐵))
3	1, 2	syl 14	. 2 ⊢ (𝐴 ⊆ 𝐵 → ran (𝐶 ↾ 𝐴) ⊆ ran (𝐶 ↾ 𝐵))
4		df-ima 4672	. 2 ⊢ (𝐶 “ 𝐴) = ran (𝐶 ↾ 𝐴)
5		df-ima 4672	. 2 ⊢ (𝐶 “ 𝐵) = ran (𝐶 ↾ 𝐵)
6	3, 4, 5	3sstr4g 3222	1 ⊢ (𝐴 ⊆ 𝐵 → (𝐶 “ 𝐴) ⊆ (𝐶 “ 𝐵))

Syntax hints:   → wi 4   ⊆ wss 3153  ran crn 4660   ↾ cres 4661   “ cima 4662

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 106  ax-ia2 107  ax-ia3 108  ax-io 710  ax-5 1458  ax-7 1459  ax-gen 1460  ax-ie1 1504  ax-ie2 1505  ax-8 1515  ax-10 1516  ax-11 1517  ax-i12 1518  ax-bndl 1520  ax-4 1521  ax-17 1537  ax-i9 1541  ax-ial 1545  ax-i5r 1546  ax-ext 2175

This theorem depends on definitions:  df-bi 117  df-3an 982  df-tru 1367  df-nf 1472  df-sb 1774  df-clab 2180  df-cleq 2186  df-clel 2189  df-nfc 2325  df-v 2762  df-un 3157  df-in 3159  df-ss 3166  df-sn 3624  df-pr 3625  df-op 3627  df-br 4030  df-opab 4091  df-xp 4665  df-cnv 4667  df-dm 4669  df-rn 4670  df-res 4671  df-ima 4672

This theorem is referenced by:  funimass1  5331  funimass2  5332  fvimacnv  5673  f1imass  5817  ecinxp  6664  sbthlem1  7016  sbthlem2  7017  iscnp4  14386  cnptopco  14390  cnntri  14392  cnrest2  14404  cnptopresti  14406  cnptoprest  14407  metcnp3  14679