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Homework Help: Trigonometry Problem

  1. Jan 14, 2015 #1
    1. The problem statement, all variables and given/known data
    Solve for x
    2sinx= 3x2 + 2x + 3

    2. Relevant equations
    Lowest value of quadratic function = -D/4a (D= Discriminant)

    3. The attempt at a solution
    I have no idea how to do it
  2. jcsd
  3. Jan 14, 2015 #2


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    2017 Award

    Staff: Mentor

    Did you draw a sketch?
    I think there is some error in the problem statement.
  4. Jan 14, 2015 #3


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    Homework Helper

    Based on your entry for #2, relevant equations, what do you know about the lowest value of the quadratic function? What is the range of 2sinx? As to mfb's point, these may be inconsistent.
  5. Jan 14, 2015 #4


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    Science Advisor

    This equation has a transcendental function equal to a polynomial. In general, there is no simple way to solve such problems. You will need to use a numerical method. (Such equations can be solved using "Lambert's W function" which is defined as the inverse function to [itex]xe^x[/itex] but converting sine to exponentials will introduce complex numbers so I would not be inclined to try that.)
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