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Math Help - trig equation

  1. #1
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    trig equation

    Solve the equation 4 + 3 sin (2x 1) = 6 for 0 < x < pi/2. please help me solve this equation
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  2. #2
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    \displaystyle 4 + 3\sin{(2x-1)} = 6

    \displaystyle 3\sin{(2x-1)} = 2

    \displaystyle \sin{(2x-1)} = \frac{2}{3}

    \displaystyle 2x-1 = \arcsin{\left(\frac{2}{3}\right)}

    \displaystyle 2x = 1 + \arcsin{\left(\frac{2}{3}\right)}

    \displaystyle x = \frac{1}{2} + \frac{1}{2}\arcsin{\left(\frac{2}{3}\right)}
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  3. #3
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    Quote Originally Posted by loraltmath View Post
    Solve the equation 4 + 3 sin (2x 1) = 6 for 0 < x < pi/2. please help me solve this equation
    sin(2x-1)=2/3

    2x-1=arcsin(2/3)

    solve for x make sure calc is in radians
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  4. #4
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    make sure calc is in radians
    thank you, but how do i do this?
    Last edited by mr fantastic; February 22nd 2011 at 05:23 PM. Reason: Added a quote tag.
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  5. #5
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    Quote Originally Posted by loraltmath View Post
    thank you, but how do i do this?
    Are you saying that you do not know what "radians" are? Do you understand what the condition you stated, " 0\le x\le \pi/2" means?

    If you are using a calculator to find arcsin(2/3), do you know how to set the "mode" of your calculator? For example, the calculator that comes with Windows has buttons that give "Degrees", "Radians", and "Grad".
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