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тригонометрическая функция Portuguese
função trigonométrica Spanish
razón trigonométrica Catalan
funcions trigonomètriques 
1
A trigonometric function (sine + cosine) with periods of 12 and 24 h was used to describe the diurnal cyclical pattern.
2
A cyclic association pattern was confirmed by trigonometric functions.
3
It wasn't all that long ago that this is what you had to do to evaluate trigonometric functions.
4
"Screw up a basic trigonometric function, and that shit eats you for breakfast."
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