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    The question

    CosX=0.7

    X=Cos^-1(0.7) = 45.6 (3 sig fig)

    Using cast can someone tell me if this is right with a -360<x<360 interval

    I got 45.6, -45.6, 314.4, - 314.4

    Is that right ?
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    Yes your solutions are correct.


    This was posted from The Student Room's iPhone/iPad App
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    (Original post by SherlockHolmes)
    Yes your solutions are correct.


    This was posted from The Student Room's iPhone/iPad App
    Is this right for an interval of -180<x<180

    Tan2X=1.2 _________> -360 <x<360
    X=Tan^-1(1.2)

    2X = 50.2, -50.2 230.2,-230.2
    X= 25.1, -25.1, 115.1, -115.1 ?
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    (Original post by User32432432)
    Is this right for an interval of -180<x<180

    Tan2X=1.2 _________> -360 <x<360
    X=Tan^-1(1.2)

    2X = 50.2, -50.2 230.2,-230.2
    X= 25.1, -25.1, 115.1, -115.1 ?
    hm your solutions are correct but I'm a little confused; is x in the interval -180 < x < 180 or -360 < x < 360 ?
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    (Original post by User32432432)
    Is this right for an interval of -180<x<180

    Tan2X=1.2 _________> -360 <x<360
    X=Tan^-1(1.2)

    2X = 50.2, -50.2 230.2,-230.2
    X= 25.1, -25.1, 115.1, -115.1 ?
    Yes your solutions are correct.
 
 
 
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