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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
Right Triangle Trigonometry
The Six Trigonometric Ratios
Sine (sin)
Definition in Right Triangle
Opposite over Hypotenuse
Ratio Interpretation
Properties of Sine
Range from 0 to 1
Increasing Function in First Quadrant
Cosine (cos)
Definition in Right Triangle
Adjacent over Hypotenuse
Ratio Interpretation
Properties of Cosine
Range from 0 to 1
Decreasing Function in First Quadrant
Tangent (tan)
Definition in Right Triangle
Opposite over Adjacent
Ratio Interpretation
Properties of Tangent
Can Take Any Real Value
Increasing Function in First Quadrant
Cosecant (csc)
Definition in Right Triangle
Hypotenuse over Opposite
Reciprocal of Sine
Properties of Cosecant
Always Greater than or Equal to 1
Undefined When Sine is Zero
Secant (sec)
Definition in Right Triangle
Hypotenuse over Adjacent
Reciprocal of Cosine
Properties of Secant
Always Greater than or Equal to 1
Undefined When Cosine is Zero
Cotangent (cot)
Definition in Right Triangle
Adjacent over Opposite
Reciprocal of Tangent
Properties of Cotangent
Can Take Any Real Value
Decreasing Function in First Quadrant
The SOH CAH TOA Mnemonic
SOH (Sine = Opposite/Hypotenuse)
CAH (Cosine = Adjacent/Hypotenuse)
TOA (Tangent = Opposite/Adjacent)
Using the Mnemonic for Problem Solving
Alternative Memory Devices
Special Right Triangles
45-45-90 Triangles
Angle Measures
Side Ratios
1 : 1 : √2
Trigonometric Values
sin 45° = cos 45° = √2/2
tan 45° = 1
Applications of 45-45-90 Triangles
30-60-90 Triangles
Angle Measures
Side Ratios
1 : √3 : 2
Trigonometric Values
Values for 30° and 60°
Applications of 30-60-90 Triangles
Deriving Special Triangle Values
Geometric Construction Methods
Algebraic Verification
Solving Right Triangles
Identifying Given Information
Known Sides and Angles
Unknown Quantities
Choosing Appropriate Strategy
Finding Unknown Side Lengths
Using Trigonometric Ratios
Selecting Appropriate Ratio
Setting Up Equations
Solving for Unknown
Using Pythagorean Theorem
When to Apply
Verification Method
Finding Unknown Angle Measures
Using Inverse Trigonometric Functions
Selecting Appropriate Inverse Function
Calculator Usage
Angle Sum Property
Sum Equals 90° for Acute Angles
Checking Solutions for Reasonableness
Angle Size Verification
Triangle Inequality
Introduction to Inverse Trigonometric Functions
Need for Inverse Functions
Finding Angles from Ratios
Reversing Trigonometric Operations
Arcsin (sin⁻¹)
Definition and Notation
Domain and Range
Domain: [-1, 1]
Range: [-90°, 90°]
Evaluating Arcsin
Calculator Methods
Special Values
Arccos (cos⁻¹)
Definition and Notation
Domain and Range
Domain: [-1, 1]
Range: [0°, 180°]
Evaluating Arccos
Calculator Methods
Special Values
Arctan (tan⁻¹)
Definition and Notation
Domain and Range
Domain: All Real Numbers
Range: (-90°, 90°)
Evaluating Arctan
Calculator Methods
Special Values
Applications of Right Triangle Trigonometry
Angle of Elevation
Definition of Angle of Elevation
Setting Up Problems
Identifying Observer and Object
Drawing Diagrams
Solving Elevation Problems
Height Calculations
Distance Calculations
Angle of Depression
Definition of Angle of Depression
Relationship to Angle of Elevation
Setting Up Problems
Solving Depression Problems
Navigation and Bearings
Understanding Bearings
True Bearings
Compass Bearings
Mathematical vs Navigational Conventions
Solving Navigation Problems
Distance and Direction
Course Corrections
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1. Foundations of Trigonometry
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3. Trigonometric Functions of Any Angle