Question

Determine the zeros of f(x) = x4 – x3 + 7x2 – 9x – 18.

Answer 1

try out the factors of 18 first

Answer 2

i dont understand the step by step process. Like what should i do first?

Answer 3

put some small factors of 18 in place of x first

Answer 4

lets say some factor n works and the expression is zero...then divide the expression by (x-n)

Answer 5

thats what i got so far and im stuck

Answer 6

now
(x^2-x+9)(x^2+9)

Answer 7

but isnt that for the diference of squares? i got (x+9)