Consider the polynomial s(x)=x2−4x+3.
(i) Explain how the value of a polynomial at a particular number can be used to decide whether that number is a zero of the polynomial.
(ii) Using the idea stated in part (i), check whether x=3 is a zero of s(x).
(iii) Similarly, check whether x=1 is a zero of s(x). State your reasoning clearly.