Check the validity of the statements given below by the method given against it.

(i) p: The sum of an irrational number and a rational number is irrational (by contradiction method).


(ii) q: If n is a real number with n > 3, then n2 > 9 (by contradiction method).


(i) Assume that the given statement p is false.


So, the statement becomes the sum of an irrational number and a rational number is rational.


Let us take for example,


Where √p is irrational number and q/r and s/t are rational numbers.


Then, is a rational number and √p is an irrational number.


This is a contradiction.


The assumption we made is wrong.


Thus, the given statement p is true.


(ii) Assume that the given statement q is false.


So, the statement becomes if n is a real number with n > 3, then n2 < 9.


From the given statement, we know that n > 3 and n is a real number.


Squaring on both sides, we get


n2 > 32


n2 > 9


This is a contradiction.


The assumption we made is wrong.


Thus, the given statement q is true.


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