Metamath Proof Explorer


Theorem dp2lt10

Description: Decimal fraction builds real numbers less than 10. (Contributed by Thierry Arnoux, 16-Dec-2021)

Ref Expression
Hypotheses dp2lt10.a ⊢ A ∈ ℕ 0
dp2lt10.b ⊢ B ∈ ℝ +
dp2lt10.1 ⊢ A < 10
dp2lt10.2 ⊢ B < 10
Assertion dp2lt10 Could not format assertion : No typesetting found for |- _ A B < ; 1 0 with typecode |-

Proof

Step Hyp Ref Expression
1 dp2lt10.a ⊢ A ∈ ℕ 0
2 dp2lt10.b ⊢ B ∈ ℝ +
3 dp2lt10.1 ⊢ A < 10
4 dp2lt10.2 ⊢ B < 10
5 df-dp2 Could not format _ A B = ( A + ( B / ; 1 0 ) ) : No typesetting found for |- _ A B = ( A + ( B / ; 1 0 ) ) with typecode |-
6 9p1e10 ⊢ 9 + 1 = 10
7 3 6 breqtrri ⊢ A < 9 + 1
8 1 nn0zi ⊢ A ∈ ℤ
9 9nn0 ⊢ 9 ∈ ℕ 0
10 9 nn0zi ⊢ 9 ∈ ℤ
11 zleltp1 ⊢ A ∈ ℤ ∧ 9 ∈ ℤ → A ≤ 9 ↔ A < 9 + 1
12 8 10 11 mp2an ⊢ A ≤ 9 ↔ A < 9 + 1
13 7 12 mpbir ⊢ A ≤ 9
14 rpssre ⊢ ℝ + ⊆ ℝ
15 14 2 sselii ⊢ B ∈ ℝ
16 10re ⊢ 10 ∈ ℝ
17 10pos ⊢ 0 < 10
18 16 17 elrpii ⊢ 10 ∈ ℝ +
19 divlt1lt ⊢ B ∈ ℝ ∧ 10 ∈ ℝ + → B 10 < 1 ↔ B < 10
20 15 18 19 mp2an ⊢ B 10 < 1 ↔ B < 10
21 4 20 mpbir ⊢ B 10 < 1
22 1 nn0rei ⊢ A ∈ ℝ
23 0re ⊢ 0 ∈ ℝ
24 23 17 gtneii ⊢ 10 ≠ 0
25 15 16 24 redivcli ⊢ B 10 ∈ ℝ
26 22 25 pm3.2i ⊢ A ∈ ℝ ∧ B 10 ∈ ℝ
27 9re ⊢ 9 ∈ ℝ
28 1re ⊢ 1 ∈ ℝ
29 27 28 pm3.2i ⊢ 9 ∈ ℝ ∧ 1 ∈ ℝ
30 leltadd ⊢ A ∈ ℝ ∧ B 10 ∈ ℝ ∧ 9 ∈ ℝ ∧ 1 ∈ ℝ → A ≤ 9 ∧ B 10 < 1 → A + B 10 < 9 + 1
31 26 29 30 mp2an ⊢ A ≤ 9 ∧ B 10 < 1 → A + B 10 < 9 + 1
32 13 21 31 mp2an ⊢ A + B 10 < 9 + 1
33 32 6 breqtri ⊢ A + B 10 < 10
34 5 33 eqbrtri Could not format _ A B < ; 1 0 : No typesetting found for |- _ A B < ; 1 0 with typecode |-