Which of the following expressions are polynomials in one variable and which are not? State reasons for your answer

(i)

(ii)

(iii)

(iv)

(v)

(i) There is only one variable x with whole number power so this polynomial in one variable

(ii) There is only one variable y with whole number power so this polynomial in one variable

(iii) There is only variable t but in 3 power of t is 1/2 which is not a whole number so 3 + t is not a polynomial

(iv) There is only one variable y but 2/y = 2y – 1 so the power is not a whole number so y + 2/y is not a polynomials

(v) There are three variable x, y and t and their powers are whole number so this polynomial in three variable