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Metamath Proof Explorer

Theorem 4re

Description: The number 4 is real. (Contributed by NM, 27-May-1999)

Ref Expression
Assertion 4re 4 ∈ ℝ

Proof

Step Hyp Ref Expression
1 df-4 ⊢ 4 = ( 3 + 1 )
2 3re ⊢ 3 ∈ ℝ
3 1re ⊢ 1 ∈ ℝ
4 2 3 readdcli ⊢ ( 3 + 1 ) ∈ ℝ
5 1 4 eqeltri ⊢ 4 ∈ ℝ