Question

prove that cube root5 is errational
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Answer 1

Explanation:

let's assume that cube root 5 is a rational number.

so we can say that a/b is some integer of cube root 5.

therefore

√5 = a/b

cubing both sides

we will get 5 x √5 = a^3/b^3

so

√5 = a^3/b^3 x 5

we can say that a^3/b^3 x 5 is rational. so cube root 5 is also rational. it contradicts that our assumption is wrong. therefore cube root 5 is irrational.

proved...

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