Trigonometry
Exploring Ratios, Identities &
Applications
Introduction to Trigonometry
• • Trigonometry is the study of relationships
between the sides and angles of triangles.
• • Widely used in physics, engineering,
architecture, navigation, and astronomy.
Trigonometric Ratios
• In a right-angled triangle:
• • sin θ = Opposite / Hypotenuse
• • cos θ = Adjacent / Hypotenuse
• • tan θ = Opposite / Adjacent
• • cosec θ = 1/sin θ
• • sec θ = 1/cos θ
• • cot θ = 1/tan θ
Values of Standard Angles
• Standard angles: 0°, 30°, 45°, 60°, 90°
• sin θ: 0, 1/2, 1/√2, √3/2, 1
• cos θ: 1, √3/2, 1/√2, 1/2, 0
• tan θ: 0, 1/√3, 1, √3, ∞
Trigonometric Identities
• Fundamental Identities:
• • sin²θ + cos²θ = 1
• • 1 + tan²θ = sec²θ
• • 1 + cot²θ = cosec²θ
Graphs of Trigonometric Functions
• • The graphs of sine, cosine, and tangent are
periodic.
• • sin and cos oscillate between -1 and 1.
• • tan θ has vertical asymptotes where cos θ =
0.
Applications in Real Life
• • Measuring heights of buildings and
mountains.
• • Navigation and astronomy.
• • Engineering and construction.
• • Physics problems involving waves and
oscillations.
Sample Problems
• Example:
• A tower casts a shadow of 20 m when the
angle of elevation of the sun is 45°.
• Height of the tower = 20 × tan(45°) = 20 m.
Quick Recap
• • Trigonometry connects angles and sides of
triangles.
• • Key ratios: sin, cos, tan.
• • Standard values and identities simplify
calculations.
• • Useful in real-life applications like heights
and distances.
Thank You!
Questions?

Trigonometry_PPT.pptx for class 10 level

  • 1.
  • 2.
    Introduction to Trigonometry •• Trigonometry is the study of relationships between the sides and angles of triangles. • • Widely used in physics, engineering, architecture, navigation, and astronomy.
  • 3.
    Trigonometric Ratios • Ina right-angled triangle: • • sin θ = Opposite / Hypotenuse • • cos θ = Adjacent / Hypotenuse • • tan θ = Opposite / Adjacent • • cosec θ = 1/sin θ • • sec θ = 1/cos θ • • cot θ = 1/tan θ
  • 4.
    Values of StandardAngles • Standard angles: 0°, 30°, 45°, 60°, 90° • sin θ: 0, 1/2, 1/√2, √3/2, 1 • cos θ: 1, √3/2, 1/√2, 1/2, 0 • tan θ: 0, 1/√3, 1, √3, ∞
  • 5.
    Trigonometric Identities • FundamentalIdentities: • • sin²θ + cos²θ = 1 • • 1 + tan²θ = sec²θ • • 1 + cot²θ = cosec²θ
  • 6.
    Graphs of TrigonometricFunctions • • The graphs of sine, cosine, and tangent are periodic. • • sin and cos oscillate between -1 and 1. • • tan θ has vertical asymptotes where cos θ = 0.
  • 7.
    Applications in RealLife • • Measuring heights of buildings and mountains. • • Navigation and astronomy. • • Engineering and construction. • • Physics problems involving waves and oscillations.
  • 8.
    Sample Problems • Example: •A tower casts a shadow of 20 m when the angle of elevation of the sun is 45°. • Height of the tower = 20 × tan(45°) = 20 m.
  • 9.
    Quick Recap • •Trigonometry connects angles and sides of triangles. • • Key ratios: sin, cos, tan. • • Standard values and identities simplify calculations. • • Useful in real-life applications like heights and distances.
  • 10.