Description: Multiplication of a number and its reciprocal. (Contributed by NM, 9-Feb-1995)
| Ref | Expression | ||
|---|---|---|---|
| Hypotheses | divclz.1 | ⊢ 𝐴 ∈ ℂ | |
| reccl.2 | ⊢ 𝐴 ≠ 0 | ||
| Assertion | recidi | ⊢ ( 𝐴 · ( 1 / 𝐴 ) ) = 1 | 
| Step | Hyp | Ref | Expression | 
|---|---|---|---|
| 1 | divclz.1 | ⊢ 𝐴 ∈ ℂ | |
| 2 | reccl.2 | ⊢ 𝐴 ≠ 0 | |
| 3 | 1 | recidzi | ⊢ ( 𝐴 ≠ 0 → ( 𝐴 · ( 1 / 𝐴 ) ) = 1 ) | 
| 4 | 2 3 | ax-mp | ⊢ ( 𝐴 · ( 1 / 𝐴 ) ) = 1 |