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Homework Help: Complicated equation!

  1. Mar 2, 2012 #1
    Hi everybody!

    I have to solve the following equation using algebraic methods: a=? such as 2x + ax > 3x + 4x for any x from ℝ.

    I solved it using analytical methods. Using The Rolle Theorem, but I don't wanna solve it in that way! The solution for a is 6
     
  2. jcsd
  3. Mar 2, 2012 #2

    Ray Vickson

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    Homework Helper

    Be careful: as written, your inequality fails for the real value x = 0. Perhaps you meant "≥". (In Mathematics, we need to be precise!) Also, of course, a solution is _any_ a ≥ 6. Perhaps the question asked for the smallest such a?

    Finally, why do you not want to use Rolle's theorem?

    RGV
     
  4. Mar 3, 2012 #3
    Yes! The smallest value for a! and there is ≥. Sorry!
    Using Rolle's theorem is quite simple to solve it... I don't wanna solve it 'cause I need a solution for it... I just wanna find an approach through we can solve it using algebraic methods!
     
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