Question

In the following exercises, identify whether each number is rational or irrational.

. (a) √25 (b) √30

Answer 1

(a) √25 rational

(b) √30 irrational

Explanation:

Note : only perfect squares have rational roots

25 = 5² then 25 is a perfect square

therefore √25 = 5 is a rational number

30 cannot be written in the form a² where ‘a’ I start a natural number then 30 is not a perfect square

Therefore √30 is irrational.