A

• acute angle, 1.1
• acute triangle, Ch. 2
• addition formulas, 3.2
• Ahmes, Ch. 1
• altitude, 2.1
• ambiguous case in Law of Sines, 2.1
• amplitude, 5.2
• amplitude envelope, 5.2
• angle, 1.1
  • acute, 1.1
  • central, 2.5
  • coterminal, 1.4
  • general, 1.4
  • included, 2.2
  • initial side of, 1.4
  • inscribed, 2.5
  • negative, 1.4
  • obtuse, 1.1
  • of incidence, 3.2
  • of transmission, 3.2
  • positive, 1.4
  • reference, 1.4
  • right, 1.1
  • straight, 1.1
  • subtended, 4.3
  • terminal side of, 1.4
• angle of depression, 1.3
• angle of elevation, 1.3
• angular speed, 4.4
• arc, 2.5
• arc cosecant, 5.3
• arc cosine, 5.3
• arc cotangent, 5.3
• arc length, 4.2
• arc secant, 5.3
• arc sine, 5.3
• arc tangent, 5.3
• area, 1.2
  • circle, 4.3
  • sector, 4.3
  • triangle, 2.4
• argument of a complex number, 6.3
• asymptote, 5.1
  • horizontal, 5.3
  • vertical, 5.1
• attractive fixed point, 6.2
• average speed, 4.4

C

• Cartesian coordinates, 1.4
• central angle, 2.5
• centripetal acceleration, 4.4
• chord, 2.5, 4.2
• circle, 1.1
  • area, 4.3
  • circumference, 4.1
  • circumscribed, 2.5
  • inscribed, 1.3, 2.5
  • segment, 4.3
  • tangent line to, 1.1
  • unit, 5.1
• circular motion, 4.4
• circumference, 4.1
• circumscribed circle, 2.5
• cis, 6.3
• Cofunction theorem, 1.2
• cofunctions, 1.2
• complementary angles, 1.1
• complex number, 6.3
  • argument of, 6.3
  • conjugate of, 6.3
  • modulus of, 6.3
  • n^th roots of, 6.3
  • trigonometric form, 6.3
• complex plane, 6.3
• congruent triangles, 1.3
• conjugate, 6.3
• conjugate angles, 1.1
• coordinates, 1.4
  • Cartesian, 1.4
  • polar, 6.4
  • rectangular, 6.4
• cosecant, 1.2
  • graph of, 5.1
• cosine, 1.2
  • graph of, 5.1
• cotangent, 1.2
  • graph of, 5.1
• coterminal angles, 1.4
• cycle, 5.2

D

• De Moivre's Theorem, 6.3
• die punch, 1.3
• distance from earth to sun, 1.3
• dodecagon, 4.2
• domain, 5.2, 5.3
• double-angle formulas, 3.3

E

• ellipsoid, 1.3
• ellipticity, 1.3
• equatorial parallax, 1.3
• equilateral triangle, 1.2
• Euclid's formula, 1.1
• even function, 1.5
• explementary angles, 1.1

F

• Fresnel coefficients, 3.2, 3.4, 3.4
• function, 5.3

G

• gears, 4.4
• gradian, 4.1
• graphs, Ch. 5
• Greek alphabet, 1.1

H

• half-angle formulas, 3.3
• Heron's formula, 2.4
  • numerical instability of, 2.4
• Hipparchus, Ch. 1
• horizontal asymptote, 5.3
• hypotenuse, 1.1

I

• identities, 3.1
  • difference of two angles, 3.2
  • double-angle, 3.3
  • half-angle, 3.3
  • product-to-sum, 3.4
  • sum of two angles, 3.2
  • sum-to-product, 3.4
• imaginary number, 6.3
  • pure, 6.3
• imaginary part, 6.3
• imaginary unit, 6.3
• included angle, 2.2
• index of refraction, 3.2
• initial side of angle, 1.4
• inscribed angle, 2.5
• inscribed circle, 1.3, 2.5
• inscribed polygon, 1.3
• inscribed triangle, 2.5
• instantaneous center of rotation, 1.3
• inverse cosecant, 5.3
• inverse cosine, 5.3
• inverse cotangent, 5.3
• inverse secant, 5.3
• inverse sine, 5.3
• inverse tangent, 5.3
• inverse trigonometric functions, 1.3, 5.3
• isosceles triangle, 1.1

L

• Law of Cosines, Ch. 2, 2.2
• Law of Sines, Ch. 2
  • ambiguous case, 2.1
• Law of Tangents, Ch. 2, 2.3
• legs of a right triangle, 1.1
• length of a line segment, 1.2
• linear speed, 4.4

M

• median of a triangle, 2.2
• minute, 1.3
• modulated wave, 5.2
• modulus, 6.3
• Mollweide's equations, 2.3

N

• negative angle, 1.4
• nth@n^th roots of a complex number, 6.3
• numerical instability, 2.4
• numerical methods, 6.2

O

• oblique triangle, Ch. 2
• obtuse angle, 1.1
• obtuse triangle, Ch. 2
• octagon, 1.3
• odd function, 1.5
• one-to-one, 5.3

P

• period of a function, 5.2
• perpendicular, 1.1
• perpendicular bisector, 2.5
• phase shift, 5.2
• phase, out of or in, 5.2
• polar axis, 6.4
• polar coordinates, 6.4
• positive angle, 1.4
• product-to-sum formulas, 3.4
• Ptolemy, Ch. 1
• Ptolemy's Theorem, 3.2
• pure imaginary number, 6.3
• Pythagorean Theorem, 1.1
• Pythagorean triple, 1.1

Q

• quadrants, 1.4

R

• radians, 4.1
• radius, 2.5
• radius of earth, 1.3
• radius of sun, 1.3
• range, 5.2, 5.3
• real part, 6.3
• rectangular coordinates, 6.4
• reference angle, 1.4
• reflection, 1.5
• regular polygon, 1.3
• revolution, 1.4
• Rhind Papyrus, Ch. 1
• right angle, 1.1
• right triangle, 1.1
• rotation, 1.5
• rpm, 4.4

S

• secant, 1.2
  • graph of, 5.1
• secant method, 6.2
• second, 1.3
• sector, 4.3
• segment, 4.3
• similar triangles, 1.1
• sine, 1.2
  • graph of, 5.1
  • unit circle definition of, 5.1
• sine-Gordon equation, 3.3
• sinusoidal curves, 5.1
• slider-crank mechanism, 1.3
• slope of a line, 1.5
• Snell's law, 3.2
• solving a triangle, 1.3
• standard position, 1.4
• straight angle, 1.1
• subtended angle, 4.3
• subtraction formulas, 3.2
• sum-to-product formulas, 3.4
• supplementary angles, 1.1

T

• tangent, 1.2
  • graph of, 5.1
• tangent line, 1.1, 1.3, 1.3
• terminal side of angle, 1.4
• Thales' Theorem, 1.1
• triangle, 1.1
  • acute, Ch. 2
  • area, 2.4
  • equilateral, 1.2
  • inscribed, 2.5
  • isosceles, 1.1
  • median of, 2.2
  • oblique, Ch. 2
  • obtuse, Ch. 2
  • right, 1.1
• trigonometric equations, 6.1
• trigonometric form, 6.3
• trigonometric functions, 1.2
  • graphs of, Ch. 5

U

• unit circle, 5.1

V

• v-block, 1.3
• vertex, 1.4
• vertical asymptote, 5.1

W

• worm thread, 1.3

X

• xaxis@x-axis, 1.4

Y

• yaxis@y-axis, 1.4
• yi@y-intercept, 1.5