Which polynomial function f(x) has a leading coefficient of 1, roots –4, 2, and 9 with multiplicity 1, and root –5 with multiplicity 3?
f(x) = 3(x + 5)(x + 4)(x – 2)(x – 9)
f(x) = 3(x – 5)(x – 4)(x + 2)(x + 9)
f(x) = (x + 5)(x + 5)(x + 5)(x + 4)(x – 2)(x – 9)
f(x) = (x – 5)(x – 5)(x – 5)(x – 4)(x + 2)(x + 9)

Respuesta :

"polynomial function f(x) has a leading coefficient of 1"

So because of that, we can eliminate A and B.

Now we have "
root –5 with multiplicity 3"

That's just product of three factors (x+5)

So D is wrong.

We are left with the only possible correct option C.

Answer:

The expression for f(x) is:

      f(x) = (x+5)(x+5)(x+5)(x+4)(x-2)(x-9)

Step-by-step explanation:

We know that for any polynomial equation with roots:

[tex]a_1,a_2,a_3,...[/tex] with multiplicity:

[tex]m_1,m_2,...[/tex]

the equation for the polynomial is given by:

[tex]f(x)=(x-a_1)^{m_1}(x-a_2)^{m_2}......[/tex]

if the leading coefficient is negative we may take '-' sign in the starting of the expression.

Here we are given that :

f(x) has a leading coefficient of 1, roots –4, 2, and 9 with multiplicity 1, and root –5 with multiplicity 3

Hence, f(x) is given by:

[tex]f(x)=(x-(-4))^{1}(x-2)^{1}(x-9)^{1}(x-(-5))^{3}\\\\\\i.e.\\\\\\f(x)=(x+4)(x-2)(x-9)(x+5)^3\\\\\\f(x)=(x+5)(x+5)(x+5)(x+4)(x-2)(x-9)[/tex]

Hence, the expression for f(x) is:

            [tex]f(x)=(x+5)(x+5)(x+5)(x+4)(x-2)(x-9)[/tex]