Trigonometry Table Class 11: Standard Values of Trigonometric Ratios
Trigonometry is an important branch of mathematics that deals with the relationship between the angles and sides of a triangle. In Class 11, students learn the standard values of trigonometric ratios, which are essential for solving various mathematical problems.

What is a Trigonometry Table?
A trigonometry table contains the standard values of the six trigonometric ratios for commonly used angles. These values help students solve trigonometric equations quickly without performing lengthy calculations.
The six trigonometric ratios are:
- Sine (sin)
- Cosine (cos)
- Tangent (tan)
- Cotangent (cot)
- Secant (sec)
- Cosecant (cosec)
Trigonometry Table (Standard Angles)
| Angle (θ) | 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 | Not Defined |
| cosec θ | Not Defined | 2 | √2 | 2/√3 | 1 |
| sec θ | 1 | 2/√3 | √2 | 2 | Not Defined |
| cot θ | Not Defined | √3 | 1 | 1/√3 | 0 |
Trigonometric Ratios Formulas
For a right-angled triangle:
- sin θ = Perpendicular / Hypotenuse
- cos θ = Base / Hypotenuse
- tan θ = Perpendicular / Base
- cosec θ = Hypotenuse / Perpendicular
- sec θ = Hypotenuse / Base
- cot θ = Base / Perpendicular
Important Trigonometric Identities
1. Pythagorean Identity
sin²θ + cos²θ = 1
2. Tan-Sec Identity
1 + tan²θ = sec²θ
3. Cot-Cosec Identity
1 + cot²θ = cosec²θ
Tips to Remember the Trigonometry Table
For Sine Values
Use the formula:
sin θ = √n / 2
where n = 0, 1, 2, 3, 4
Thus:
- sin 0° = √0/2 = 0
- sin 30° = √1/2 = 1/2
- sin 45° = √2/2 = 1/√2
- sin 60° = √3/2
- sin 90° = √4/2 = 1
For Cosine Values
Reverse the sine values:
- cos 0° = 1
- cos 30° = √3/2
- cos 45° = 1/√2
- cos 60° = 1/2
- cos 90° = 0
Applications of Trigonometry
Trigonometry is used in:
- Engineering
- Architecture
- Navigation
- Astronomy
- Physics
- Surveying
- Computer Graphics