Question

prove that 7-√5 is irrational
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Answer 1

Answer:

Let 7√5 be a rational number.

So,

7√5 = p/q.

(p and q are co-prime number and q ≠ 0)

=> √5 = p/7q

As, we can see that p/7q ia rational so √5 should also be rational. But this contradict the fact that √5 is irrational.

So, by this we can say that 7√5 is irrational number.