State, giving the reason, whether the following expressions are polynomials or not.

(1) b² – 25

(2)

(3)

(1) The given algebraic expression is a polynomial in one variable because all the powers of x are whole numbers.

In this given polynomial the power of b is +2 and 0.

Hence these are whole powers of b and hence this expression is a polynomial.

(2) y^1/2 -5y + 18 is not a polynomial because in this given equation the first term contains the power of y as 1/2 where 1/2 is not a whole number. So the given algebraic expression is not a polynomial.

(3) 7/m - 2 is not a polynomial because in this given equation the second term becomes 7 × m^-1 where -1 is not a whole number. So the given algebraic expression is not a polynomial.