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Homework Help: I want check my answer ()()()

  1. Oct 11, 2009 #1
    I want check my answer ()()()

    Attached Files:

  2. jcsd
  3. Oct 11, 2009 #2


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    Science Advisor

    For 59 you have "- x3" when you should be subtracting the square.

    For 60 you have "[itex]\sqrt{x}+ \sqrt{x}+ \sqrt{x}[/itex]" for "add three times the square root". That will work but should be written more simply as "[itex]3\sqrt{x}[/itex]".

    The others are correct.
  4. Oct 11, 2009 #3
    my dear

    #59 what is wrong ?

    # 60
    F(x) = -8xccube + 3square root of 3

    now is ok?
  5. Oct 11, 2009 #4


    Staff: Mentor

    #59 "subtracts the square of the domain element", not the cube of it, as you have.
    #60 Correct. F(x) = -8x3 + 3[itex]\sqrt{3}[/itex]
  6. Oct 11, 2009 #5


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    Homework Helper

    In #59 the question says "...then subtract the square of the domain element..." (maybe the underline is the key here :wink:)
    But you have subtracted the cube.
    the square ---> x2
    the cube ----> x3

    See the dilemma?

    For #60 yes that is ok now.
  7. Oct 11, 2009 #6
    thanks very much for helping me
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