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Trigonometry
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Angle measures and circles
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Intro to radians
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Arc length and sector formulas
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Converting between radians and degrees
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Degrees-minutes-seconds
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Right triangles and trig
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Intro to trigonometry
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Intro to the six basic trig functions
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Evaluating the six basic trig functions
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Evaluate the remaining basic trig functions
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Reciprocal and quotient identities
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Cofunction identities
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Special right triangles
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Area of an equilateral triangle
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Solving right triangles
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Circumradii of equilateral and isosceles triangles
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Graphing trig functions
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Graphing sin and cos
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Graphing tan and cot
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Graphing sec and csc
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Unit circle
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Finding the point on the unit circle
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Evaluating trig functions and solving trig equations using the unit circle
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Evaluating trig functions using coterminal and reference angles
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Proofs using the unit circle
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Signs of trig functions
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Inverse trig functions
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Composition of trig functions
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Evaluating inverse trig functions using the unit circle
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Evaluating inverse trig functions using a calculator
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Find the inverse of a trigonometric function
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Graphing inverse trigonometric functions
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Non-right triangles and trig
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Sine rule for area of a triangle
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Area of a segment
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Heron's formula
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Law of cosines
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Parallelogram law
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Stewart's theorem
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Law of sines
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Trigonometric identities
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Double and half angle formulas
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Solving trig equations
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Solving trigonometric equations by graphing
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Solving trigonometric equations by factoring out the GCD
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Finding general solutions to trig equations
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Solving harder trig equations by factoring
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Solving trigonometric equations quadratic in form
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t-results
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Solving trig equations by factoring trinomials
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Sum and difference formulas
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Auxiliary angle method
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Finding the acute angle between two lines
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Product-to-sum and sum-to-product formulas
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Proving inverse trig identities
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Power reducing trig identities
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Pythagorean identities
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Disproving trigonometric identities by counterexample
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Even-odd trig identities
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Polar coordinates
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Plotting polar points
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Graphing polar equations
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Converting between polar and Cartesian form
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Complex numbers in polar form
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Multiplying and dividing complex numbers in polar form
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Proving de Moivre's theorem
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Powers of complex numbers using De Moivre's theorem
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Roots of complex numbers using De Moivre's theorem
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Hyperbolic and inverse hyperbolic functions
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Proving inverse hyperbolic identities
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Intro to hyperbolic functions
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Proving hyperbolic identities
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Solving hyperbolic equations
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Trigonometry
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Trigonometric identities
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Product-to-sum and sum-to-product formulas
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Other resources
Proof: Sum to product identity for sine
\(\sin(A) + \sin(B) = 2\sin\left(\dfrac{A + B}{2}\right)\cos\left(\dfrac{A - B}{2}\right)\)
2978
PROVE THIS, sum-to-product identity for sine, bprp retro!
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