8.Let a and b be integers and d a positive integer. (a) Prove that if d...

8.Let a and b be integers and d a positive integer.
(a) Prove that if d divides a and d divides b, then d divides both a + b and a − b.
(b) Is the converse of the above true? If so, prove it. If not, give a specific example of a, b, d showing
that the converse is false.

9. Let a, b, c, m, n be integers. Prove that if a divides each of b and c, then a divides nb + mc.

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Expert Solution

This is the required solution for the given question no 8 (part a,b,c) .Hope it will help you . Please give a Thumbs up .Thank you.

Colby Messinger answered 1 year ago

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