Metamath Proof Explorer


Theorem f1imass

Description: Taking images under a one-to-one function preserves subsets. (Contributed by Stefan O'Rear, 30-Oct-2014)

Ref Expression
Assertion f1imass ⊢ F : A ⟶ 1-1 B ∧ C ⊆ A ∧ D ⊆ A → F C ⊆ F D ↔ C ⊆ D

Proof

Step Hyp Ref Expression
1 simplrl ⊢ F : A ⟶ 1-1 B ∧ C ⊆ A ∧ D ⊆ A ∧ F C ⊆ F D → C ⊆ A
2 1 sseld ⊢ F : A ⟶ 1-1 B ∧ C ⊆ A ∧ D ⊆ A ∧ F C ⊆ F D → a ∈ C → a ∈ A
3 simplr ⊢ F : A ⟶ 1-1 B ∧ C ⊆ A ∧ D ⊆ A ∧ F C ⊆ F D ∧ a ∈ A → F C ⊆ F D
4 3 sseld ⊢ F : A ⟶ 1-1 B ∧ C ⊆ A ∧ D ⊆ A ∧ F C ⊆ F D ∧ a ∈ A → F ⁡ a ∈ F C → F ⁡ a ∈ F D
5 simplll ⊢ F : A ⟶ 1-1 B ∧ C ⊆ A ∧ D ⊆ A ∧ F C ⊆ F D ∧ a ∈ A → F : A ⟶ 1-1 B
6 simpr ⊢ F : A ⟶ 1-1 B ∧ C ⊆ A ∧ D ⊆ A ∧ F C ⊆ F D ∧ a ∈ A → a ∈ A
7 simp1rl ⊢ F : A ⟶ 1-1 B ∧ C ⊆ A ∧ D ⊆ A ∧ F C ⊆ F D ∧ a ∈ A → C ⊆ A
8 7 3expa ⊢ F : A ⟶ 1-1 B ∧ C ⊆ A ∧ D ⊆ A ∧ F C ⊆ F D ∧ a ∈ A → C ⊆ A
9 f1elima ⊢ F : A ⟶ 1-1 B ∧ a ∈ A ∧ C ⊆ A → F ⁡ a ∈ F C ↔ a ∈ C
10 5 6 8 9 syl3anc ⊢ F : A ⟶ 1-1 B ∧ C ⊆ A ∧ D ⊆ A ∧ F C ⊆ F D ∧ a ∈ A → F ⁡ a ∈ F C ↔ a ∈ C
11 simp1rr ⊢ F : A ⟶ 1-1 B ∧ C ⊆ A ∧ D ⊆ A ∧ F C ⊆ F D ∧ a ∈ A → D ⊆ A
12 11 3expa ⊢ F : A ⟶ 1-1 B ∧ C ⊆ A ∧ D ⊆ A ∧ F C ⊆ F D ∧ a ∈ A → D ⊆ A
13 f1elima ⊢ F : A ⟶ 1-1 B ∧ a ∈ A ∧ D ⊆ A → F ⁡ a ∈ F D ↔ a ∈ D
14 5 6 12 13 syl3anc ⊢ F : A ⟶ 1-1 B ∧ C ⊆ A ∧ D ⊆ A ∧ F C ⊆ F D ∧ a ∈ A → F ⁡ a ∈ F D ↔ a ∈ D
15 4 10 14 3imtr3d ⊢ F : A ⟶ 1-1 B ∧ C ⊆ A ∧ D ⊆ A ∧ F C ⊆ F D ∧ a ∈ A → a ∈ C → a ∈ D
16 15 ex ⊢ F : A ⟶ 1-1 B ∧ C ⊆ A ∧ D ⊆ A ∧ F C ⊆ F D → a ∈ A → a ∈ C → a ∈ D
17 2 16 syld ⊢ F : A ⟶ 1-1 B ∧ C ⊆ A ∧ D ⊆ A ∧ F C ⊆ F D → a ∈ C → a ∈ C → a ∈ D
18 17 pm2.43d ⊢ F : A ⟶ 1-1 B ∧ C ⊆ A ∧ D ⊆ A ∧ F C ⊆ F D → a ∈ C → a ∈ D
19 18 ssrdv ⊢ F : A ⟶ 1-1 B ∧ C ⊆ A ∧ D ⊆ A ∧ F C ⊆ F D → C ⊆ D
20 19 ex ⊢ F : A ⟶ 1-1 B ∧ C ⊆ A ∧ D ⊆ A → F C ⊆ F D → C ⊆ D
21 imass2 ⊢ C ⊆ D → F C ⊆ F D
22 20 21 impbid1 ⊢ F : A ⟶ 1-1 B ∧ C ⊆ A ∧ D ⊆ A → F C ⊆ F D ↔ C ⊆ D