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Homework Help: Sketch f(x)=x^3-2x^2+5

  1. Oct 16, 2007 #1
    1. The problem statement, all variables and given/known data
    sketch f(x)=x^3-2x^2+5

    2. Relevant equations

    3. The attempt at a solution
    i tried to uses synthetic division to bring it down to a lower power, but i cant remember what to do cuz i dont know any of the factors...
  2. jcsd
  3. Oct 16, 2007 #2


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    Homework Helper

    Well first you would try to find factors such that f(a)=0, if f(a)=0 then (x-a) is a factor of f(x).

    Seeing as how the last number there is 5, then you should try,1,-1,-5,5 and see if any are zero.

    If you do not find it to be zero,then either it has complex roots or non-integer roots.
    find where it cuts the f(x)-axis and x-axis. Find turning points(and whether they are max or min points) and try to sketch. If you need more help, reply back
  4. Oct 17, 2007 #3
    it didnt work.... and seeing as this was a hw question i dont think my teacher would have made it so complex...did i set up the synthetic division correctly?

    5 | 1 -2 0 5
  5. Oct 17, 2007 #4
    yea...i set it up right..turns out that i didnt need to find the intercepts, and couldve just aproximated a sketch
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