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MathWorld subject trigonometric functions
MathWorld subject trigonometric identities
MathWorld subject general trigonometry
mathworld subject triangle properties
d sin(x)/dx
d cos(x)/dx
d tan(x)/dx
d arctan(x)/dx
d arcsin(x)/dx
Weierstrass substitution
prosthaphaeresis formulas
law of cosines
law of sines
law of tangents
solve sqrt(3)*sin(x)+cos(x)=1 for x
spherical trigonometry
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