Question

show that n2-1is divisible by8,if n is an odd positive integer

Answer 1

Divisibility rule for 8 should be followed.

If the last three digits of a whole number are divisible by 8 then the number is divisible by 8.

ex. 1240.

last three digits @re 240

240/8 = 30

so 1240 is divisible by 8.

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