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How do i solve this?

  1. Oct 3, 2004 #1
    x^2+7x>6+2x^3...I tried many times..i cant solve this :grumpy: ...please help
     
  2. jcsd
  3. Oct 3, 2004 #2
    x^2 + 7x > 6 + 2x^3 = -2x^3 + x^2 + 7x - 6 > 0

    Try solving for:
    -2x^3 + x^2 + 7x - 6 = 0
     
  4. Oct 3, 2004 #3
    I cant solve that sorry...could you help any further?
     
  5. Oct 3, 2004 #4

    Tide

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    I noticed the sum of the coefficients is 1 so (x-1) is a factor:

    [tex]2x^3-x^2-7x+6 = (x-1)(x+2)(2x-3)[/tex]

    That should get you started!
     
  6. Oct 6, 2004 #5
    try it,
    x^2 + 7x>6x + 2x^3
    or, 2x^3 - x^2 -x<0
    or, x(2x^2 - x - 1)<0
    this implies, either x<0 or (2x^2 - x - 1) <0
    as the expression is negative which is only possible if one of the term is negative.
     
  7. Oct 6, 2004 #6

    Integral

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    You have read the problem incorrectly. It should read
    [tex] x^2 + 7x > 6 + 2x^3 [/tex]
     
    Last edited: Oct 6, 2004
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