Proof: Algebra 17b

Let's prove the following theorem:

(s / 2) / s = 1 / 2

Proof:

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Proof Table
# Claim Reason
1 s / 2 = s ⋅ (1 / 2) s / 2 = s ⋅ (1 / 2)
2 (s / 2) / s = (s ⋅ (1 / 2)) / s if s / 2 = s ⋅ (1 / 2), then (s / 2) / s = (s ⋅ (1 / 2)) / s
3 (s ⋅ (1 / 2)) / s = (s ⋅ (1 / 2)) ⋅ (1 / s) (s ⋅ (1 / 2)) / s = (s ⋅ (1 / 2)) ⋅ (1 / s)
4 (s ⋅ (1 / 2)) ⋅ (1 / s) = (s ⋅ (1 / s)) ⋅ (1 / 2) (s ⋅ (1 / 2)) ⋅ (1 / s) = (s ⋅ (1 / s)) ⋅ (1 / 2)
5 s ⋅ (1 / s) = 1 s ⋅ (1 / s) = 1
6 (s ⋅ (1 / s)) ⋅ (1 / 2) = 1 ⋅ (1 / 2) if s ⋅ (1 / s) = 1, then (s ⋅ (1 / s)) ⋅ (1 / 2) = 1 ⋅ (1 / 2)
7 1 ⋅ (1 / 2) = 1 / 2 1 ⋅ (1 / 2) = 1 / 2
8 (s ⋅ (1 / s)) ⋅ (1 / 2) = 1 / 2 if (s ⋅ (1 / s)) ⋅ (1 / 2) = 1 ⋅ (1 / 2) and 1 ⋅ (1 / 2) = 1 / 2, then (s ⋅ (1 / s)) ⋅ (1 / 2) = 1 / 2
9 (s ⋅ (1 / 2)) ⋅ (1 / s) = 1 / 2 if (s ⋅ (1 / 2)) ⋅ (1 / s) = (s ⋅ (1 / s)) ⋅ (1 / 2) and (s ⋅ (1 / s)) ⋅ (1 / 2) = 1 / 2, then (s ⋅ (1 / 2)) ⋅ (1 / s) = 1 / 2
10 (s ⋅ (1 / 2)) / s = 1 / 2 if (s ⋅ (1 / 2)) / s = (s ⋅ (1 / 2)) ⋅ (1 / s) and (s ⋅ (1 / 2)) ⋅ (1 / s) = 1 / 2, then (s ⋅ (1 / 2)) / s = 1 / 2
11 (s / 2) / s = 1 / 2 if (s / 2) / s = (s ⋅ (1 / 2)) / s and (s ⋅ (1 / 2)) / s = 1 / 2, then (s / 2) / s = 1 / 2

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