okay medal will be awarded to whoever gives the best answer.

What polynomial has roots of –6, 1, and 4

A. x3 – 9x2 – 22x + 24

B. x3 – x2 – 26x – 24

C. x3 + x2 – 26x + 24

D. x3 + 9x2 + 14x – 24

Question

okay medal will be awarded to whoever gives the best answer.

What polynomial has roots of –6, 1, and 4

A. x3 – 9x2 – 22x + 24 


B. x3 – x2 – 26x – 24 


 C. x3 + x2 – 26x + 24 


 D. x3 + 9x2 + 14x – 24

parthkohli · Answer

If $\rm blah$ is a root, then $x - \rm blah$ is a factor. We might know that a polynomial is just a product of factors.

parthkohli · Answer

Can you write the three factors down? I'd write down one for ya.

$-6$ is a root, so $x - (-6) =  x + 6$ is a factor.

anonymous · Answer

yea but I cant figure it out

anonymous · Answer

x=6 x-1 x-4

parthkohli · Answer

@Luis_Rivera Eh no...

parthkohli · Answer

More like $(x + 6)(x -1)(x - 4)$!

anonymous · Answer

hmm so now what

parthkohli · Answer

Now just expand $(x + 6)\times (x - 1) \times (x - 4)$

anonymous · Answer

so (x+6)(x-1) and that answer time (x-4)

anonymous · Answer

nope but I wouldnt mind some

anonymous · Answer

the expression which give the result zero when substituted with all the three roots

anonymous · Answer

so I multiply (x+6)(x-1) and got x2 + 5x - 6 now i multiply that by (x-4)?

anonymous · Answer

so the answers c

parthkohli · Answer

@Luis_Rivera lol no!

parthkohli · Answer

I mean, the factors are NOT $x-6,x+1,x+4$ but their respective conjugates.