Question

please answer fast.​

Answer 1

it's an irrational number.......

when u solve it ,u will get 2/√10

and we know√10is irrational number....

hope it helps you

and

Answer 2

$\boxed{\red{\bold{ Answer : \sqrt0.4 }}}$

√0.4 because when we not able to find the root of any no. then answer of root of no. is same as question