Trigonometry formulas for Class 11 and 12
Here is the list of formulas for trigonometry
- Basic Trigonometric Function Formulas
- Reciprocal Identities
- Periodicity Identities
- Cofunction Identities
- Trigonometric Identities
- Trigonometry Table
- Trigonometric function
- Trigonometry of Sum or difference in To Product
- Trigonometry of product into sum or difference
- To express trigonometric ratios of 2A in terms of trigonometric ratios of A
- Trigonometric ratios of 3A in terms of A
Basic Trigonometric Function Formulas
- sin θ = Opposite Side/Hypotenuse
- cos θ = Adjacent Side/Hypotenuse
- tan θ = Opposite Side/Adjacent Side
- sec θ = Hypotenuse/Adjacent Side
- cosec θ = Hypotenuse/Opposite Side
- cot θ = Adjacent Side/Opposite Side
Reciprocal Identities
The Reciprocal Identities are given as:
- cosec θ = 1/sin θ
- sec θ = 1/cos θ
- cot θ = 1/tan θ
- sin θ = 1/cosec θ
- cos θ = 1/sec θ
- tan θ = 1/cot θ
Periodicity Identities
- sin (π/2 – A) = cos A & cos (π/2 – A) = sin A
- sin (π/2 + A) = cos A & cos (π/2 + A) = – sin A
- sin (3π/2 – A) = – cos A & cos (3π/2 – A) = – sin A
- sin (3π/2 + A) = – cos A & cos (3π/2 + A) = sin A
- sin (π – A) = sin A & cos (π – A) = – cos A
- sin (π + A) = – sin A & cos (π + A) = – cos A
- sin (2π – A) = – sin A & cos (2π – A) = cos A
- sin (2π + A) = sin A & cos (2π + A) = cos A
Cofunction Identities
- sin(90°−x) = cos x
- cos(90°−x) = sin x
- tan(90°−x) = cot x
- cot(90°−x) = tan x
- sec(90°−x) = cosec x
- cosec(90°−x) = sec x
Trigonometric Identities
• Sin²A+Cos²A = 1
• Sin²A = 1-Cos²A
• Cos²A = 1-Sin²A
• Sec²A = 1+tan²A
• Sec²A-tan²A = 1
• Sec²A-1 = tan²A
• CoSec²A = 1+Cot²A
• CoSec²A-1 = Cot²A
• CoSec²A-Cot²A = 1
Trigonometry Table
Trigonometric function
To Evaluate sin (A+B) formula
Sin(A+B) = SinA SinB + CosA SinB
To Evaluate cos (A+B) formula
Cos(A+B) = CosA CosB – SinA SinB
To Evaluate tan (A+B) formula
To Evaluate cot (A+B) formula
To Evaluate tan (A+B+C) formula
To Evaluate cot (A+B+C) formula
To Evaluate sin (A-B) formula
Sin(A-B) = SinA SinB – CosA SinB
To Evaluate cos(A-B) formula
Cos(A-B) = CosA CosB + SinA SinB
To Evaluate tan (A-B) formula
To Evaluate cot (A-B) formula
Trigonometry of Sum or difference in To Product
Trigonometry of product into sum or difference
To express trigonometric ratios of 2A in terms of trigonometric ratios of A
Trigonometric ratios of 3A in terms of A
