Comprehensive Trigonometry and Graphing Guide

Special Right Triangles

  • 45-45-90 Triangle:     * Angles: 45∘45^{\circ}, 45∘45^{\circ}, and 90∘90^{\circ}.     * Side proportions: The legs are equal to 11, and the hypotenuse is sqrt2\\sqrt{2}.

  • 30-60-90 Triangle:     * Angles: 30∘30^{\circ}, 60∘60^{\circ}, and 90∘90^{\circ}.     * Side proportions: The side opposite the 30∘30^{\circ} angle is 11, the side opposite the 60∘60^{\circ} angle is sqrt3\\sqrt{3}, and the hypotenuse is 22.

The Unit Circle and Quadrants

  • Unit Circle Coordinates:     * 0∘0^{\circ} or 360∘360^{\circ} (2pi2\\pi): (1,0)(1, 0)     * 90∘90^{\circ} (fracpi2\\frac{\\pi}{2}): (0,1)(0, 1)     * 180∘180^{\circ} (pi\\pi): (−1,0)(-1, 0)     * 270∘270^{\circ} (frac3pi2\\frac{3\\pi}{2}): (0,−1)(0, -1)

  • Quadrant Signs (ASTC Rule):     * Quadrant I (A - All): All trigonometric functions (sin(x)\\sin(x), cos(x)\\cos(x), tan(x)\\tan(x), csc(x)\\csc(x), sec(x)\\sec(x), cot(x)\\cot(x)) are positive (+,+)(+,+).     * Quadrant II (S - Sine): Only Sine and Cosecant are positive (−,+)(-,+).     * Quadrant III (T - Tangent): Only Tangent and Cotangent are positive (−,−)(-,-).     * Quadrant IV (C - Cosine): Only Cosine and Secant are positive (+,−)(+,-).

Trigonometric Identities

  • Cofunction Identities:     * sin(90−theta)=cos(theta)\\sin(90 - \\theta) = \\cos(\\theta)     * cos(90−theta)=sin(theta)\\cos(90 - \\theta) = \\sin(\\theta)     * tan(90−theta)=cot(theta)\\tan(90 - \\theta) = \\cot(\\theta)     * csc(90−theta)=sec(theta)\\csc(90 - \\theta) = \\sec(\\theta)     * Specific Example: cos(90−20)=sin(20)\\cos(90 - 20) = \\sin(20)

  • Even and Odd Identities:     * sin(−theta)=−sin(theta)\\sin(-\\theta) = -\\sin(\\theta)     * cos(−theta)=cos(theta)\\cos(-\\theta) = \\cos(\\theta)     * tan(−theta)=−tan(theta)\\tan(-\\theta) = -\\tan(\\theta)     * csc(−theta)=−csc(theta)\\csc(-\\theta) = -\\csc(\\theta)

Trigonometric Functions and Graphing Properties

  • General Sine/Cosine Form:     * Standard Equation: y=Asin(Bx)y = A \\sin(Bx) or y=Acos(Bx)y = A \\cos(Bx)     * AA: Amplitude     * textPeriod=frac2piB\\text{Period} = \\frac{2\\pi}{B}

  • Secant Function (y=sec(x)y = \\sec(x)):     * Domain: xneqfracπ2+pinx \\neq \\frac{\pi}{2} + \\pi n     * Range: (−∞,−1]cup[1,infty)(-\infty, -1] \\cup [1, \\infty)     * Period: 2pi2\\pi

  • Cosecant Function (y=csc(x)y = \\csc(x)):     * Domain: xneq0+pinx \\neq 0 + \\pi n     * Range: (−∞,−1]cup[1,infty)(-\infty, -1] \\cup [1, \\infty)     * Period: 2pi2\\pi

  • Tangent Function (y=tan(x)y = \\tan(x)):     * Period: pi\\pi

  • Cotangent Function (y=cot(x)y = \\cot(x)):     * Domain: xneq0+pinx \\neq 0 + \\pi n     * Range: (−∞,infty)(-\infty, \\infty)     * Period: pi\\pi

  • Function Transformations Noted:     * y=−cos(x)y = -\\cos(x)     * y=−tan(x)y = -\\tan(x)     * y=−cot(x)y = -\\cot(x)

Additional Topics

  • Inverse Trigonometric Functions:     * Included as a topic of study, categorized as "Inverse/Arc Trig Functions".

  • Miscellaneous Notes:     * UFCPS9 (notation/reference marker)     * SING     * F-Sing     * Values noted: 0.21−60.21-6, 0.300∘0.300^{\circ}, 0.03380.0338.