[tex]\bf sin(\theta)=\cfrac{opposite}{hypotenuse}
=\cfrac{y}{r}
=\cfrac{1}{csc(\theta)}
\\\\\\
% cosine
\boxed{cos(\theta)=\cfrac{adjacent}{hypotenuse}
=\cfrac{x}{r}
=\cfrac{1}{sec(\theta)}}
\\\\\\
% tangent
tan(\theta)=\cfrac{opposite}{adjacent}
=\cfrac{y}{x}
=\cfrac{sin(\theta)}{cos(\theta)}
\\\\\\
[/tex]
[tex]\bf cot(\theta)=\cfrac{adjacent}{opposite}
=\cfrac{x}{y}
=\cfrac{cos(\theta)}{sin(\theta)}
\\\\\\
% cosecant
csc(\theta)=\cfrac{hypotenuse}{opposite}
=\cfrac{r}{y}
=\cfrac{1}{sin(\theta)}
\\\\\\
% secant
sec(\theta)=\cfrac{hypotenuse}{adjacent}
=\cfrac{r}{x}
=\cfrac{1}{cos(\theta)}[/tex]
