Description: The real numbers form a star ring. (Contributed by Thierry Arnoux, 19-Apr-2019)
Ref | Expression | ||
---|---|---|---|
Assertion | recrng | ⊢ ℝfld ∈ *-Ring |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | rebase | ⊢ ℝ = ( Base ‘ ℝfld ) | |
2 | refldcj | ⊢ ∗ = ( *𝑟 ‘ ℝfld ) | |
3 | refld | ⊢ ℝfld ∈ Field | |
4 | isfld | ⊢ ( ℝfld ∈ Field ↔ ( ℝfld ∈ DivRing ∧ ℝfld ∈ CRing ) ) | |
5 | 3 4 | mpbi | ⊢ ( ℝfld ∈ DivRing ∧ ℝfld ∈ CRing ) |
6 | 5 | simpri | ⊢ ℝfld ∈ CRing |
7 | 6 | a1i | ⊢ ( ⊤ → ℝfld ∈ CRing ) |
8 | cjre | ⊢ ( 𝑥 ∈ ℝ → ( ∗ ‘ 𝑥 ) = 𝑥 ) | |
9 | 8 | adantl | ⊢ ( ( ⊤ ∧ 𝑥 ∈ ℝ ) → ( ∗ ‘ 𝑥 ) = 𝑥 ) |
10 | 1 2 7 9 | idsrngd | ⊢ ( ⊤ → ℝfld ∈ *-Ring ) |
11 | 10 | mptru | ⊢ ℝfld ∈ *-Ring |