PROOF 01
Prove.
(−1) × (−1) = 1
On the integers ℤ. Two operations: + and ×.
Definition D1
−1 is the number satisfying 1 + (−1) = 0.
Proof.
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PROOF 01
(−1) × (−1) = 1
On the integers ℤ. Two operations: + and ×.
Definition D1
−1 is the number satisfying 1 + (−1) = 0.
Proof.
Related labs