Question

If two zeroes of the polynomial f(x)=x3−4x2−3x+12 are √3 and -√3 then find its third zero.

Answer 1

Third zero is 4

Explanation:

The polynomial is;

f(x) = x³ − 4x² − 3x + 12

We are given 2 zeros which are √3 and -√3.

This means that a factor of the polynomial will b; (x² - 3) because when it is equated to zero, x will be √3 and -√3.

Now, to get the other factor of the polynomial, we have to divide x³ − 4x² − 3x + 12 by (x² - 3) using long division method.

I have attached this long division method and we have the third factor as; (x - 4)

Equating to zero, we have x = 4 as the third zero of the polynomial