Thread: Which of the following is a factor of

Which of the following is a factor of?

P(x) = x^4+ 6x^3+ 9x^2+ 3x + 9 ?


a) x - 2
b) x + 2
c) x + 3
d) x - 3
e) None of the above

Use the Factor Theorem, namely that for any Polynomial function , if then is a factor.

the answer is x+3

P(x) = (-3)^4+ 6x^(-3)+ 9(-3)^2+ 3(-3) + 9= 0

?

Originally Posted by dragovx

the answer is x+3

P(x) = (-3)^4+ 6x^(-3)+ 9(-3)^2+ 3(-3) + 9= 0

?

You're on the right track.

If you're testing as a factor, then ...










as required.


Therefore is a factor.

Originally Posted by dragovx

Which of the following is a factor of?

P(x) = x^4+ 6x^3+ 9x^2+ 3x + 9 ?


a) x - 2
b) x + 2
c) x + 3
d) x - 3
e) None of the above

The rational roots theorem allows the first two to be eliminated with no further consideration and Descartes rule of signs tell you that this has no positive roots which eliminates x-3 leaving only one case to check.

CB