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Thread: trigonometry equations

  1. #1

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    trigonometry equations

    Evaluate
    [tan(180+x)]/[sin(180-x)] times [tan(90+x)]/[cos^2(180+x)] times sin(-x) - 1

    =(tanx)/(sinx) times (-tanx)/[cos^2(x)] times -sinx - 1

    = 1/cosx times -sinx/cos^3(x) times -sinx -1

    =sin^2(x)/cos^4(x) - 1

    im stuck at this point can someone help me out.

  2. #2
    vbuggy krtxmrtz's Avatar
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    Re: trigonometry equations

    Evaluating each factor separately:

    tan(180 + x)/sin(180 + x) = tan(x)/sin(x) = 1/cos(x)

    tan(90 + x)/cos2(180 + x) = (-1/tan(x)) / cos2(x)

    sin(-x) = -sin(x)

    Grouping all factors you get:

    (1/cos(x))*(1/-tan(x))*(-sin(x)/cos2(x)) - 1 =

    1/cos2(x) - 1 = tan2(x)
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    Re: trigonometry equations

    right thank you very much

  4. #4
    vbuggy krtxmrtz's Avatar
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    Re: trigonometry equations

    Quote Originally Posted by fiery123
    right thank you very much
    You're welcome. Don't forget to rate the post!
    Lottery is a tax on people who are bad at maths
    If only mosquitoes sucked fat instead of blood...
    To do is to be (Descartes). To be is to do (Sartre). To be do be do (Sinatra)

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