Question

1*5

Answer 1

Any integer (positive and negative numbers), except 0, times 1 equal itself.

Answer 2

1 if you mean 1^5, and 5 if you mean 1 x 5

Answer 3

1 * 5 = 1*1*1*1*1
take
1(1*1*1*1)
=(1*1) + (1*1) + (1*1) + (1*1) + (1*1)
=2(1*1) + 2(1*1) + (1*1)
=2 + 2 +1
=5