Question

prove that 5 x 7 x 9 x 11 x 13 + 13 is a rational number .

Answer 1

As we can see,

(5×7×9×11×13) belongs to rational , as the product of rational terms is also rational .

and we know that 13 is an integer therefore

by this we conclude that when we add this two ration terms then the product is also rational

as,

Rational + Rational = Always Rational