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    Re: Classic Trig Log Sight Reduction Revisited
    From: Greg Rudzinski
    Date: 2014 May 30, 12:26 -0700

    Attached is a further refined index card sight reduction using the Ix cosine sum method. Notice for this reduction that the S value is larger than 90 degrees which requires using the cosine complement as a negative value for summing. Calculators automatical show the correct value. For natural trig tables there will be a little extra work.

    The third column is the double cosine sum = sine product of standard formula

    The fourth column is the quad cosine sum = cosine product of standard formula

    Same rules apply for final summing of values.
    Add if same name, subtract if contrary for LHA 270 to 360;000 to 090
    Subtract if same name, add if contrary for LHA 090 to 270

    Greg Rudzinski
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