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 Question from owais, a teacher: according to definition of irrational number "a number which cannot be expressed in p/q form is called irrational number" square root of 2 is a irrational number but if i round off the digit correct to two decimal places so it becomes 1.41 and we can easily convert into p/q form so it is a rational number ??? i have confusion plz help me

Hi,

You are correct, 1.41 can easily be converted to a common fraction $\large \frac{p}{q}$ and hence it is a rational number. However 1.41 is not $\sqrt2,$ it is only an approximation of $\sqrt2.$ As you said it is only "correct to two decimal places".

Penny

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