Q8 of 32 Page 20

Prove that √3 + √5 is irrational.

Let be any rational number x


squaring both sides







as x is a rational number so x2 is also a rational number, 8 and 2 are rational nos. , so √15 must also be a rational number as the quotient of two rational numbers is rational


but, √15 is an irrational number


We arrive at a contradiction this shows that our supposition was wrong


so √3 + √5 is not a rational number.


Hence, proved.


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