\(\begin{aligned}\href{/posts/cosine}{\cos}(\alpha) &= \frac{\text{adjacent}}{\text{hypotenuse}} \\ &= \frac{\href{/posts/sine}{\sin}(\alpha)}{\href{/posts/tangent}{\tan}(\alpha)}\end{aligned}\)

Also see Sine and Tangent (Trigonometry); Trigonometry.

(“Sine and Cosine” 2022)

Graph of \(\href{/posts/cosine}{\cos}\)

Bibliography