Rational Linear Combinations of Pure Geodetic Angles
Rational Linear Combinations of Pure Geodetic Angles
A "pure geodetic" angle is an angle with any of its six squared trigonometric functions rational (or infinite). This Demonstration shows how an angle whose tangent is of the form /+/ can be expressed as a rational linear combination of pure geodetic angles and an integral multiple of , that is, it finds rational and such that + is a sum of , where and a rational linear combination of and .
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π/2
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tan
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kπ/2
k∈{-1,0,1}
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tan
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tan
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