Question

prove that 7 root 5 is irrational number​

Answer 1

Answer:

Let us assum that 7root5 is an irrational number ,say r

7root5=r

root5=r/7

Therefore r and 7 are rational number

r/7 is a rational number

This show that

root5 is rational number

But we know that root5 is an irrational number

Therefore our assumption was wrong

Hence 7root5 is an irrational number

Answer 2

Let 7 root 5 is rational no.

7 root 5 = p/q , q not =0 ,p and q is a coprime no., root 5 =p/7q

since p,q,7 are integers

so root 5 is integers

so our assumption is wrong

so 7 root 5 is irrational