Question

is a be a rational number and b be an irrational number is ab necessarly an irrational number??

Answer 1

Heyaa..

Yes..!! The product of a rational number and an irrational number is necessarily an irrational number..

The proof can be given by taking contradiction.

EXAMPLE :

Let a = 7 ( rational number )

And b = √2 ( irrational number )

So.. ab = 7 × √2

ab = 7 √2 ( irrational number )

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Hope it helps...

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