Verified answer

Natural numbers are positive integers. Depending on the definition of the natural numbers in your course/class, 0 may or may not be included.

Irrational numbers are numbers that cannot be written as a fraction.

Let A be the set that you defined.

(i) all the natural numbers in A are 0/2 = 0 (if 0 is in N), Sqrt[25]/5 = 1, and 17. -Sqrt[36] = -6, but isn't positive, so it's not in the natural numbers.

(ii) Pi is an irrational number, so a multiple of it is too. So -5pi is irrational. Sqrt[2] is irrational, so 1 + Sqrt[2] is too.

List Of All Natural Numbers