Solve:

x^3+3x^2-5x-15=0

(a)List all potential zeros

(b)Do synthetic division to solve then finsh

Thanks

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- December 5th 2005, 06:05 PMjwaingoldZeros and Synthetic Division
Solve:

x^3+3x^2-5x-15=0

(a)List all potential zeros

(b)Do synthetic division to solve then finsh

Thanks - December 5th 2005, 09:32 PMCaptainBlack
Lets look at the very similar equation:

First thing to do is sketch the graph of:

to see if we can find the approximate location of its zeros.

From the sketch in the attachment we see that this has zeros

near -2.7, -2, and +2.7. Trying these out we find that -2 is

an exact root of the cubic. So we may write:

in this case turns out to be:

quadratic formula to find its roots, and hence its linear factors.

So:

Your problem can be solved in a similar manner.

RonL