Description: Alternate proof of 0re . (Contributed by NM, 19-Feb-2005) (Proof modification is discouraged.) (New usage is discouraged.)
Ref | Expression | ||
---|---|---|---|
Assertion | 0reALT | ⊢ 0 ∈ ℝ |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | ax-1cn | ⊢ 1 ∈ ℂ | |
2 | 1 | subidi | ⊢ ( 1 − 1 ) = 0 |
3 | 1re | ⊢ 1 ∈ ℝ | |
4 | 3 3 | resubcli | ⊢ ( 1 − 1 ) ∈ ℝ |
5 | 2 4 | eqeltrri | ⊢ 0 ∈ ℝ |