Question

show that 1/ root 7 is irrational no.

Answer 1

let 1/root 7 be rational no.
1/root 7=p/q
1/root 7=a/b ( where a and b are Co primes)
root 7= 1a/b
since a and b are integer definitely 1a/b is rational no. also root 7 is also rational no....so 1/root 7 is irrational..... hence proved..

Answer 2

Root 7 is irrational so root 7 divided by 7 is also irrational.
That's why 1/root 7 is also irrational.