Starting from (-1) × 5, write various products showing some pattern to show (-1) ×(-1)=1

In this question, we have


- 1 × 5 = - 5


- 1 × 4 = - 4 = - 5 + 1


- 1 × 3 = - 3 = - 4 + 1


- 1 × 2 = 2 = - 3 + 1


- 1 × 1 = - 1 = - 2 + 1


- 1 × 0 = 0 = - 1 + 1


Therefore,


- 1 × (-1) = 0 + 1 = 1


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