In Class 11 Mathematics (Trigonometric Functions), the triple angle formulas are crucial for simplifying complex equations and solving integration problems in Class 12. The formula for sin(3x) is one of the most frequently used identities.
This formula is particularly useful in Calculus (Integration). Because integrating sin³(x) directly is difficult, students use this formula to rewrite sin³(x) as (3sin(x) - sin(3x)) / 4, which is very easy to integrate.
The formula to expand sin(3x) entirely in terms of sin(x) is:
sin(3x) = 3 sin(x) - 4 sin³(x)
(You can also write this using theta: sin(3θ) = 3sinθ - 4sin³θ).
The derivation relies on splitting 3x into (2x + x) and using the compound angle formula:
The formula for cos(3x) is almost the exact reverse of the sin(3x) formula. **cos(3x) = 4 cos³(x) - 3 cos(x)**.
What is the Value of tan 90°? — Undefined (Not Defined)
tan 90° is undefined (not defined). sin 90°=1, cos 90°=0, and tan=sin/cos=1/0=undefined. As angle→90°, tan→∞. Full explanation with unit circle.
Time Conversions – Hours, Weeks, Months
Learn all important time conversions: 1 hour in seconds, 1 year in weeks, 9 months in weeks, 444 days in months, 1 inch in mm.
1 Tola to Gram — Tola Conversion Table
1 Tola = 11.664 grams. Traditional Indian unit of mass used for gold. Also equals 12 masha, 96 ratti, 0.375 troy ounce. Full conversion table included.
Formulas for Sin C + Sin D and Sin 3θ
Class 11 Math: Memorize the sum-to-product formulas for Trigonometry (Sin C + Sin D) and the multiple angle formula for Sin 3θ.
Basic Trigonometry Questions and Answers
Practice basic trigonometry questions and answers for Class 10 Maths. Solve problems using SOH CAH TOA, trigonometric ratios, and standard angles.
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