Skip to main content\(\require{cancel}\newcommand{\colorlinecolor}{blue!95!black!30}
\newcommand{\bwlinecolor}{black!30}
\newcommand{\thelinecolor}{\colorlinecolor}
\newcommand{\colornamesuffix}{}
\newcommand{\linestyle}{[thick, \thelinecolor]}
\newcommand{\bbm}{\begin{bmatrix}}
\newcommand{\ebm}{\end{bmatrix}}
\newcommand{\ds}{\displaystyle}
\newcommand{\thet}{\theta}
\newcommand{\norm}[1]{\left\lVert#1\right\rVert}
\newcommand{\vnorm}[1]{\left\lVert\vec #1\right\rVert}
\newcommand{\dotp}[2]{\vec #1 \,\boldsymbol{\cdot}\, \vec #2}
\newcommand{\proj}[2]{\operatorname{proj}_{\,\vec #2}{\,\vec #1}}
\newcommand{\crossp}[2]{\vec #1 \times \vec #2}
\newcommand{\veci}{\vec i}
\newcommand{\vecj}{\vec j}
\newcommand{\veck}{\vec k}
\newcommand{\vecu}{\vec u}
\newcommand{\vecv}{\vec v}
\newcommand{\vecw}{\vec w}
\newcommand{\vecx}{\vec x}
\newcommand{\vecy}{\vec y}
\newcommand{\abs}[1]{\left\lvert #1\right\rvert}
\newcommand{\noin}{\noindent}
\newcommand{\vx}[1][]{\vec{x}_{#1}}
\newcommand{\vxp}{\vec{x}_p}
\newcommand{\vu}{\vec{u}}
\newcommand{\vvv}{\vec{v}}
\newcommand{\vy}{\vec{y}}
\newcommand{\vz}{\vec{z}}
\newcommand{\vb}{\vec{b}}
\newcommand{\vw}{\vec{w}}
\newcommand{\veone}{\vec{e}_1}
\newcommand{\vetwo}{\vec{e}_2}
\newcommand{\vethree}{\vec{e}_3}
\newcommand{\vei}{\vec{e}_i}
\newcommand{\ven}[1]{\vec{e}_{#1}}
\newcommand{\zero}{\vec{0}}
\newcommand{\arref}{\overrightarrow{\text{rref}}}
\newcommand{\tta}{A}
\newcommand{\ttb}{B}
\newcommand{\ttc}{C}
\newcommand{\ttd}{D}
\newcommand{\ttm}{M}
\newcommand{\ttx}{X}
\newcommand{\tti}{I}
\newcommand{\tty}{Y}
\newcommand{\ttp}{P}
\newcommand{\ttat}{A^T}
\newcommand{\ttbt}{B^T}
\newcommand{\ttct}{C^T}
\newcommand{\ttdt}{D^T}
\newcommand{\ttmt}{M^T}
\newcommand{\ttxt}{X^T}
\newcommand{\ttit}{I^T}
\newcommand{\ttyt}{Y^T}
\newcommand{\ttai}{A^{-1}}
\newcommand{\ttbi}{B^{-1}}
\newcommand{\ttxi}{X^{-1}}
\newcommand{\ttpi}{P^{-1}}
\newcommand{\ttaxb}{\tta\vx=\vb}
\newcommand{\ttaxo}{\tta\vx=\zero}
\newcommand{\eyetwo}{\begin{bmatrix}1\amp 0\\0\amp 1\end{bmatrix}}
\newcommand{\eyethree}{\begin{bmatrix}1\amp 0\amp 0\\0\amp 1\amp 0\\0\amp 0\amp 1\end{bmatrix}}
\newcommand{\eyefour}{\begin{bmatrix}1\amp 0\amp 0\amp 0\\0\amp 1\amp 0\amp 0\\0\amp 0\amp 1\amp 0\\0\amp 0\amp 0\amp 1\end{bmatrix}}
\newcommand{\tto}{\textbf{0}}
\newcommand{\lda}{\lambda}
\newcommand{\TT}{[\, T\, ]}
\newcommand{\R}{\mathbb{R}}
\newcommand{\bvm}{\begin{vmatrix}}
\newcommand{\evm}{\end{vmatrix}}
\newcommand{\tr}{\operatorname{tr}}
\newcommand{\lt}{<}
\newcommand{\gt}{>}
\newcommand{\amp}{&}
\definecolor{fillinmathshade}{gray}{0.9}
\newcommand{\fillinmath}[1]{\mathchoice{\colorbox{fillinmathshade}{$\displaystyle \phantom{\,#1\,}$}}{\colorbox{fillinmathshade}{$\textstyle \phantom{\,#1\,}$}}{\colorbox{fillinmathshade}{$\scriptstyle \phantom{\,#1\,}$}}{\colorbox{fillinmathshade}{$\scriptscriptstyle\phantom{\,#1\,}$}}}
\)
Section B.1 Trigonometry Reference
Subsection B.1.1 Definitions of the Trigonometric Functions
Unit Circle Definition.
\(\sin \theta = y\) |
\(\cos \theta = x\) |
|
\(\ds\csc \theta = \frac1y\) |
\(\ds\sec \theta = \frac1x\) |
|
\(\ds\tan \theta = \frac yx\) |
\(\ds\cot \theta = \frac xy\) |
Right Triangle Definition.
\(\ds\sin \theta = \frac{\text{O} }{\text{H} }\) |
\(\ds\csc \theta = \frac{\text{H} }{\text{O} }\) |
|
\(\ds\cos \theta = \frac{\text{A} }{\text{H} }\) |
\(\ds\sec \theta = \frac{\text{H} }{\text{A} }\) |
|
\(\ds\tan \theta = \frac{\text{O} }{\text{A} }\) |
\(\ds\cot \theta = \frac{\text{A} }{\text{O} }\) |
Subsection B.1.2 Common Trigonometric Identities
\(\displaystyle \sin ^2x+\cos ^2x= 1\)
\(\displaystyle \tan^2x+ 1 = \sec^2 x\)
\(\displaystyle 1 + \cot^2x=\csc^2 x\)
List B.1.1. Pythagorean Identities
\(\displaystyle \sin 2x = 2\sin x\cos x\)
\begin{align*}
\cos 2x \amp = \cos^2x - \sin^2 x \amp \amp \\
\amp = 2\cos^2x-1 \amp \amp \\
\amp = 1-2\sin^2x \amp \amp
\end{align*}
\(\displaystyle \tan 2x = \frac{2\tan x}{1-\tan^2 x}\)
List B.1.2. Double Angle Formulas
\(\displaystyle \sin\left(\frac{\pi}{2}-x\right) = \cos x\)
\(\displaystyle \cos\left(\frac{\pi}{2}-x\right) = \sin x\)
\(\displaystyle \tan\left(\frac{\pi}{2}-x\right) = \cot x\)
\(\displaystyle \csc\left(\frac{\pi}{2}-x\right) = \sec x\)
\(\displaystyle \sec\left(\frac{\pi}{2}-x\right) = \csc x\)
\(\displaystyle \cot\left(\frac{\pi}{2}-x\right) = \tan x\)
List B.1.3. Cofunction Identities
\(\displaystyle \sin(-x) = -\sin x\)
\(\displaystyle \cos (-x) = \cos x\)
\(\displaystyle \tan (-x) = -\tan x\)
\(\displaystyle \csc(-x) = -\csc x\)
\(\displaystyle \sec (-x) = \sec x\)
\(\displaystyle \cot (-x) = -\cot x\)
List B.1.4. Even/Odd Identities
\(\displaystyle \sin^2 x = \frac{1-\cos 2x}{2}\)
\(\displaystyle \cos^2 x = \frac{1+\cos 2x}{2}\)
\(\displaystyle \tan^2x = \frac{1-\cos 2x}{1+\cos 2x}\)
List B.1.5. Power-Reducing Formulas
\(\displaystyle \sin x+\sin y = 2\sin \left(\frac{x+y}2\right)\cos\left(\frac{x-y}2\right)\)
\(\displaystyle \sin x-\sin y = 2\sin \left(\frac{x-y}2\right)\cos\left(\frac{x+y}2\right)\)
\(\displaystyle \cos x+\cos y = 2\cos \left(\frac{x+y}2\right)\cos\left(\frac{x-y}2\right)\)
\(\displaystyle \cos x-\cos y = -2\sin \left(\frac{x+y}2\right)\sin\left(\frac{x-y}2\right)\)
List B.1.6. Sum to Product Formulas
List B.1.7. Product to Sum Formulas
\(\displaystyle \sin x\sin y = \frac12 \big(\cos(x-y) - \cos (x+y)\big)\)
\(\displaystyle \cos x\cos y = \frac12\big(\cos (x-y) +\cos (x+y)\big)\)
\(\displaystyle \sin x\cos y = \frac12 \big(\sin(x+y) + \sin (x-y)\big)\)
List B.1.8. Angle Sum/Difference Formulas
\(\displaystyle \sin (x\pm y) = \sin x\cos y \pm \cos x\sin y\)
\(\displaystyle \cos (x\pm y) = \cos x\cos y \mp \sin x\sin y\)
\(\displaystyle \tan (x\pm y) = \frac{\tan x\pm \tan y}{1\mp \tan x\tan y}\)