Ex 1.4,3 - Chapter 1 Class 9 Number Systems

Last updated at August 14, 2026 by

Ex 1.4, 3 - Recall, pi is defined as ratio of circumference - Ex 1.4

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Ex1.5, 3 Recall, is defined as the ratio of the circumference (say c) of a circle to its diameter (say d). That is, = / . This seems to contradict the fact that is irrational. How will you resolve this contradiction? = / is a rational number when c & d both are rational numbers But the c & d we calculate is not exactly a rational number and either c or d or both can be irrational numbers, Since, / = Irrational So, is irrational.

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