Find a cubic polynomial whose zeros are , 1 and –3.

Let the zeros of the polynomial be a, b and c

Where a = 1/2, b = 1 and c = - 3


The cubic polynomial can be calculated as follows:


x3 – (a + b + c) x2 + (ab + bc + ca) x – abc


Putting the values of a, b and c in the above equation we get:


= x3 – (1/2 + 1 - 3) x2 + (1/2 – 3 – 3/2)x – (- 3/2)


= x3 – (-3/2) x2 – 4x + 3/2


= 2x3 + 3x2 – 8x + 3


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