Q2 of 40 Page 25

Prove that 3 + √5 is an irrational number.

Let us assume that 3 + √5 is a rational number



where, b≠0 and a, b are integers




∵ a, b are integers ∴ a – 3b is also integer


is rational which cannot be possible


∵ which is an irrational number


∵ it is contradicting our assumption ∴ the assumption was wrong


Hence, 3 + √5 is an irrational number


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