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VCE Stuff => VCE Mathematics => VCE Mathematics/Science/Technology => VCE Subjects + Help => VCE Mathematical Methods CAS => Topic started by: kaanonball on February 03, 2009, 09:50:51 pm

Title: Polynomial proof
Post by: kaanonball on February 03, 2009, 09:50:51 pm: The question

Prove that the expression $x^3 + (k - 1)x^2 + (k - 9)x - 7$ is divisible by x + 1 for all values of k.

do i just show that $P(-1) = 0$ ?
Title: Re: Polynomial proof
Post by: nerd on February 03, 2009, 09:53:53 pm: Yeppo! Spot on...You should see that the k's cancel themselves out!
Title: Re: Polynomial proof
Post by: kaanonball on February 03, 2009, 09:58:52 pm: oks cool, ty