enSCIntro to Trigonometry13
Sine: y/r
Cosine: x/r
Tangent: y/x
Cosecant: r/y or 1/y
Secant: r/x or 1/x
Cotangent: x/y
Quadrantal Angles: 0°, 90°, 180°, 270°, 360°
Right triangle: triangle with 2 acute angles and 1 right angle
Hypotenuse: longest side of right triangle
Even property: sec(-150°)= sec 150°
Odd property: tan(-3π/2)= -tan 3π/2
Periodic: repeating after a certain period
Phase shift: ϕ/k