Let P(x)=2x3−5x2−4x+3.
(i) Evaluate P(3), P(−1) and P(21), showing all steps.
(ii) From your calculations in part (i), identify which of the numbers 3, −1 and 21 are zeros of P(x).
(iii) How many distinct x-intercepts does the graph of y=P(x) have at the values checked above? State them clearly.