Proof Index
TOC
Courses
Subreddit
Blog
Search
▾
Trigonometry
▸
Angle measures and circles
•
Intro to radians
•
Arc length and sector formulas
•
Converting between radians and degrees
•
Degrees-minutes-seconds
▸
Right triangles and trig
•
Intro to trigonometry
•
Intro to the six basic trig functions
•
Evaluating the six basic trig functions
•
Evaluate the remaining basic trig functions
•
Reciprocal and quotient identities
•
Cofunction identities
•
Special right triangles
•
Area of an equilateral triangle
•
Solving right triangles
•
Circumradii of equilateral and isosceles triangles
▸
Graphing trig functions
•
Graphing sin and cos
•
Graphing tan and cot
•
Graphing sec and csc
▸
Unit circle
•
Finding the point on the unit circle
•
Evaluating trig functions and solving trig equations using the unit circle
•
Evaluating trig functions using coterminal and reference angles
•
Proofs using the unit circle
•
Signs of trig functions
▸
Inverse trig functions
•
Composition of trig functions
•
Evaluating inverse trig functions using the unit circle
•
Evaluating inverse trig functions using a calculator
•
Find the inverse of a trigonometric function
•
Graphing inverse trigonometric functions
▸
Non-right triangles and trig
•
Sine rule for area of a triangle
•
Area of a segment
•
Heron's formula
•
Law of cosines
•
Parallelogram law
•
Stewart's theorem
•
Law of sines
▾
Trigonometric identities
•
Double and half angle formulas
▸
Solving trig equations
•
Solving trigonometric equations by graphing
•
Solving trigonometric equations by factoring out the GCD
•
Finding general solutions to trig equations
•
Solving harder trig equations by factoring
•
Solving trigonometric equations quadratic in form
•
t-results
•
Solving trig equations by factoring trinomials
•
Sum and difference formulas
•
Auxiliary angle method
•
Finding the acute angle between two lines
•
Product-to-sum and sum-to-product formulas
•
Proving inverse trig identities
•
Power reducing trig identities
•
Pythagorean identities
•
Disproving trigonometric identities by counterexample
•
Even-odd trig identities
▸
Polar coordinates
•
Plotting polar points
•
Graphing polar equations
•
Converting between polar and Cartesian form
▸
Complex numbers in polar form
•
Multiplying and dividing complex numbers in polar form
•
Proving de Moivre's theorem
•
Powers of complex numbers using De Moivre's theorem
•
Roots of complex numbers using De Moivre's theorem
▸
Hyperbolic and inverse hyperbolic functions
•
Proving inverse hyperbolic identities
•
Intro to hyperbolic functions
•
Proving hyperbolic identities
•
Solving hyperbolic equations
›
Trigonometry
›
Trigonometric identities
›
Auxiliary angle method
›
Other resources
Simplifying the sum of two wave functions using the auxiliary angle method
YouTube videos
26268
Auxiliary Angle - Basic Idea
Eddie Woo
28062
Auxiliary Angle - Natural Forms
Eddie Woo
26043
Auxiliary Angle: Natural Forms (1 of 3)
Eddie Woo
26703
Auxiliary Angle: Natural Forms (2 of 3)
Eddie Woo
27671
Introduction to Auxiliary Angle (1 of 2: Adding 2 Waves)
Eddie Woo
26246
Introduction to Auxiliary Angle (2 of 2: Using an Identity)
Eddie Woo
26811
Auxiliary Angle: Natural Forms (3 of 3)
Eddie Woo