Metamath Proof Explorer
Description: Multiplication of a number and its reciprocal. (Contributed by SN, 25-Nov-2025)
|
|
Ref |
Expression |
|
Hypotheses |
sn-rereccld.a |
⊢ ( 𝜑 → 𝐴 ∈ ℝ ) |
|
|
sn-rereccld.z |
⊢ ( 𝜑 → 𝐴 ≠ 0 ) |
|
Assertion |
rerecid2 |
⊢ ( 𝜑 → ( ( 1 /ℝ 𝐴 ) · 𝐴 ) = 1 ) |
Proof
| Step |
Hyp |
Ref |
Expression |
| 1 |
|
sn-rereccld.a |
⊢ ( 𝜑 → 𝐴 ∈ ℝ ) |
| 2 |
|
sn-rereccld.z |
⊢ ( 𝜑 → 𝐴 ≠ 0 ) |
| 3 |
1 2
|
sn-rereccld |
⊢ ( 𝜑 → ( 1 /ℝ 𝐴 ) ∈ ℝ ) |
| 4 |
1 2
|
rerecid |
⊢ ( 𝜑 → ( 𝐴 · ( 1 /ℝ 𝐴 ) ) = 1 ) |
| 5 |
1 3 4
|
remulinvcom |
⊢ ( 𝜑 → ( ( 1 /ℝ 𝐴 ) · 𝐴 ) = 1 ) |