What are the zeros of the polynomial function f(x) = x3 - 10x2 + 24x? I just want to know the name of the process to find the zeros.

Respuesta :


f(x) = x³- 10x² + 24x

f(x) = x ( x² + 10x + 24)

f(x) = x (x + 6)(x+4)

x=0


-----------------
x+6 = 0
x = 0-6
x= -6


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x+4 = 0
x = 0-4
x= -4

zero's would be: 0, -6 and -4,
So it is your third choice down.

Answer:

A zero of a function is a number, when plugged in for the variable, makes the function equal to zero.

Then, the roots of a polynomial P(x) are values of x such that P(x) = 0.

Given the polynomial function: [tex]f(x)=x^3-10x^2+24x[/tex]

By the rational theorem process,  gives us the following possible roots:  0, [tex]\pm 1[/tex], [tex]\pm 2[/tex],  [tex]\pm 3[/tex] ,  [tex]\pm 4[/tex],  [tex]\pm 6[/tex],  [tex]\pm 8[/tex],  [tex]\pm 12[/tex] and  [tex]\pm 24[/tex]

for x =0

[tex]f(0)=0^3-10(0)^2+24(0)=0[/tex]

Now, our polynomial become:

[tex]x(x^2-10x+24)[/tex] = 0

Then, we factors the remaining quadratic equation, factoring by grouping , using the facts 4+6 = 10 and [tex]4 \cdot 6 = 24[/tex]

[tex]x(x^2-6x-4x+24)[/tex] = 0

[tex]x(x(x-6)-4(x-6))[/tex] =0

[tex]x((x-6)(x-4))[/tex] =0

Zero product property states that if xy = 0 then either a =0 or b =0.

by zero product property;

⇒ x = 0, x-6=0 and x-4 = 0

Hence, x = 0 , x = 4 and x =6 are the zeros of the given polynomial function.