(50 POINTS! HELP!)

y=x^3-4x^2+9x-36 Find the roots(zeros) i got 4,3i, and -3i but i dont know how to write the steps to the answer. someone please solve it and write the steps on how to get their. I'll give brainliest to whoever has the best answer with enough steps but not too many.

Respuesta :

Answer:

The roots of the given equation is x=4,3i,-3i

Step-by-step explanation:

The given cubic equation is

[tex]y=x^3-4x^2+9x-36[/tex]

To find the roots we have to equate the equation to zero

ie, [tex]x^3-4x^2+9x-36=0[/tex]

It can be done by using Synthetic division method

Therfore [tex](x-1) is not a factor or root

now put x=-1

Therfore [tex](x-1) is not a factor or root

similarly let x=2,-2,3,-3 all not equal to zero so the are not roots.

let x-4 is a factor of given equation

then it satifies the equation ie (x-4) is a root

And it may be written as

[tex](x-4)(x^2+9)