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    Hi,

    Any help re-arranging the equation below would be greatly appreciated

    The following equation needs re-arranging to work out alpha (a)

    Phase max = 90 - (2 * tan-1 (sqrt a))

    In the actual problem my phase max = 14.14 and I know that the value of alpha (a) should work out to be 0.6072
    I need to be able to derive the equation above in an upcoming exam so any help would be appreciated

    Thanks

    Dave
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    14.14 - 90 = 2 \tan^{-1}(\sqrt{a}) so \tan(\frac{90-14.14}{2})^2 = a. (I had to interpret that as being degrees, not radians; I assume that's what you wanted.)
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    (Original post by db52174)
    Hi,

    Any help re-arranging the equation below would be greatly appreciated

    The following equation needs re-arranging to work out alpha (a)

    Phase max = 90 - (2 * tan-1 (sqrt a))

    In the actual problem my phase max = 14.14 and I know that the value of alpha (a) should work out to be 0.6072
    I need to be able to derive the equation above in an upcoming exam so any help would be appreciated

    Thanks

    Dave
    I make it 0.6073 not 0.6072
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    (Original post by joostan)
    I make it 0.6073 not 0.6072
    I put that down to a rounding error in deriving 14.14 - OP, it's usually better to work with fractions rather than decimals where possible, or at least many more significant figures than you need in the final answer.
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    (Original post by Smaug123)
    I put that down to a rounding error in deriving 14.14 - OP, it's usually better to work with fractions rather than decimals where possible, or at least many more significant figures than you need in the final answer.
    I also figured as much, though for phase - I swear its best to work in radians.
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    (Original post by joostan)
    I also figured as much, though for phase - I swear its best to work in radians.
    Yep, radians are much better in almost all cases.
 
 
 
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