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Mathematics
Trigonometry
1. Foundations of Trigonometry
2. Right Triangle Trigonometry
3. Trigonometric Functions of Any Angle
4. Graphs of Trigonometric Functions
5. Trigonometric Identities
6. Inverse Trigonometric Functions
7. Solving Trigonometric Equations
8. Applications of Trigonometry
Applications of Trigonometry
Law of Sines
Statement of Law of Sines
a/sin A = b/sin B = c/sin C
Alternative Forms
Proof of Law of Sines
Area Method
Geometric Derivation
Solving AAS Triangles
Angle-Angle-Side Cases
Finding Unknown Angle
Finding Unknown Sides
Solving ASA Triangles
Angle-Side-Angle Cases
Solution Strategy
The Ambiguous Case (SSA)
Side-Side-Angle Configuration
Determining Number of Solutions
No Solution Cases
One Solution Cases
Two Solution Cases
Solving for All Possible Triangles
Geometric Interpretation
Law of Cosines
Statement of Law of Cosines
c² = a² + b² - 2ab cos C
Alternative Forms for Other Sides
Proof of Law of Cosines
Coordinate Geometry Method
Vector Method
Solving SAS Triangles
Side-Angle-Side Cases
Finding Unknown Side
Finding Remaining Angles
Solving SSS Triangles
Side-Side-Side Cases
Finding All Angles
Verification Methods
Relationship to Pythagorean Theorem
Special Case When C = 90°
Generalization Concept
Area of Triangles
Area Using Sine
Formula: Area = ½ab sin C
Derivation from Basic Area Formula
Applications to Oblique Triangles
Heron's Formula
Statement: Area = √[s(s-a)(s-b)(s-c)]
Semi-perimeter Definition
Derivation Process
When to Use Heron's Formula
Computational Considerations
Choosing Appropriate Area Formula
Given Information Analysis
Efficiency Considerations
Introduction to Vectors
Definition of Vector
Magnitude and Direction
Geometric Representation
Distinction from Scalars
Vector Notation
Component Form
Magnitude Notation
Unit Vector Notation
Vector Operations
Vector Addition
Parallelogram Method
Component Method
Properties of Addition
Vector Subtraction
Geometric Interpretation
Component Method
Scalar Multiplication
Effect on Magnitude
Effect on Direction
Dot Product
Definition: a⃗ · b⃗ = |a⃗||b⃗|cos θ
Component Formula
Properties of Dot Product
Commutative Property
Distributive Property
Applications of Dot Product
Angle Between Vectors
Formula Using Dot Product
Calculating Angles
Perpendicular Vectors
Parallel Vectors
Polar Coordinates
Polar Coordinate System
Origin (Pole) and Polar Axis
Distance and Angle Coordinates
Notation (r, θ)
Plotting Points in Polar Coordinates
Positive and Negative r Values
Angle Measurement Conventions
Multiple Representations
Converting Between Coordinate Systems
Polar to Rectangular
x = r cos θ
y = r sin θ
Rectangular to Polar
r = √(x² + y²)
θ = arctan(y/x) with quadrant adjustment
Graphing Polar Equations
Basic Polar Curves
Circles: r = a
Lines Through Origin: θ = α
Cardioids: r = a(1 + cos θ)
Rose Curves: r = a cos(nθ)
Limaçons: r = a + b cos θ
Symmetry Tests
Polar Axis Symmetry
Line θ = π/2 Symmetry
Origin Symmetry
Graphing Strategies
Table of Values Method
Symmetry Utilization
Complex Numbers in Trigonometric Form
Complex Plane
Real Axis and Imaginary Axis
Plotting Complex Numbers
Geometric Interpretation
Polar Form of Complex Numbers
Modulus (Absolute Value)
r = |z| = √(a² + b²)
Argument (Angle)
θ = arg(z)
Principal Argument
Trigonometric Form
z = r(cos θ + i sin θ)
Euler's Notation: z = re^(iθ)
Converting Between Forms
Rectangular to Polar Form
Polar to Rectangular Form
Handling Different Quadrants
Operations in Polar Form
Multiplication of Complex Numbers
Multiply Moduli, Add Arguments
(r₁∠θ₁)(r₂∠θ₂) = r₁r₂∠(θ₁ + θ₂)
Division of Complex Numbers
Divide Moduli, Subtract Arguments
(r₁∠θ₁)/(r₂∠θ₂) = (r₁/r₂)∠(θ₁ - θ₂)
De Moivre's Theorem
Statement: [r(cos θ + i sin θ)]ⁿ = rⁿ(cos nθ + i sin nθ)
Proof Outline
Applications to Powers
Computing High Powers
Simplifying Calculations
Roots of Complex Numbers
nth Roots Formula
ⁿ√r[cos((θ + 2πk)/n) + i sin((θ + 2πk)/n)]
Finding All nth Roots
k = 0, 1, 2, ..., n-1
Geometric Interpretation
Regular n-gon Vertices
Symmetry Properties
Roots of Unity
Special Case: nth Roots of 1
Applications in Algebra
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7. Solving Trigonometric Equations
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1. Foundations of Trigonometry