Respuesta :
We have the following functions:
 f (x) = x3 - 3x2 - 13x + 15
 f (x) = x4 + 3x3 - 8x2 + 5x - 25
 f (x) = x3 - 2x2 - x + 2
 f (x) = -x3 + 13x - 12
 Factoring we have:
 f (x) = x3 - 3x2 - 13x + 15 -------> x + 3
 f (x) = x4 + 3x3 - 8x2 + 5x - 25 -> x + 5
 f (x) = x3 - 2x2 - x + 2 ------------> x - 2
 f (x) = -x3 + 13x - 12 -------------> x + 4
 f (x) = x3 - 3x2 - 13x + 15
 f (x) = x4 + 3x3 - 8x2 + 5x - 25
 f (x) = x3 - 2x2 - x + 2
 f (x) = -x3 + 13x - 12
 Factoring we have:
 f (x) = x3 - 3x2 - 13x + 15 -------> x + 3
 f (x) = x4 + 3x3 - 8x2 + 5x - 25 -> x + 5
 f (x) = x3 - 2x2 - x + 2 ------------> x - 2
 f (x) = -x3 + 13x - 12 -------------> x + 4
Answer: Â Â x + 3 Â is factor of [tex]x^3-3x^2-13x+15[/tex],
 x + 5  is factor of [tex]x^4 + 3x^3 - 8x^2 + 5x - 25 [/tex],
x - 2  is factor of  [tex]x^3 - 2x^2 - x + 2[/tex]
And,  x + 4  is factor  [tex]-x^3 + 13x - 12[/tex]
Step-by-step explanation:
Since if for a polynomial f(x), x-a is a factor then f(a)=0, ( because x=a is the zero of the polynomial)
Here, for  [tex]x^3-3x^2-13x+15[/tex],
If x=-3 then  [tex]x^3-3x^2-13x+15= -3^3-3(-3)^2-13\times -3+15 =0[/tex]
Therefore x-3 is the factor of [tex]x^3-3x^2-13x+15[/tex].
At x=-5 [tex]x^4 + 3x^3 - 8x^2 + 5x - 25[/tex] is equal to zero.
Therefore, x+5 is the factor of [tex]x^4 + 3x^3 - 8x^2 + 5x - 25[/tex].
At x=2 [tex]x^3 - 2x^2 - x + 2[/tex] is equal to zero.
Therefore, x-2 is the factor of [tex]x^3 - 2x^2 - x + 2[/tex].
At x=-4 [tex]-x^3 + 13x - 12[/tex] is equal to zero.
Therefore, x+4 is the factor of [tex]-x^3 + 13x - 12[/tex].