Find a polynomial function that has the given zeros Show wor
Solution
Given that the polynomial has zeros 4i, -4i, -1.
Need to find the polynomial.
Let the polynomial is P(x).
P(x) = (x-(4i))(x-(-4i))(x-(-1))
= (x-4i)(x+4i)(x+1)
= [x2 - (4i)2](x+1) ( since (a+b)(a-b) = a2 - b2 )
= [x2 - 16i2](x+1)
= [x2 - 16(-1)](x+1) (i2 = -1)
= [x2 + 16](x+1)
= x2(x+1) + 16(x+1)
= x3 + x2 + 16x +16
Therefore, required polynomial P(x) = x3 + x2 + 16x +16
