Home | About Mathguru | Advertisements | Teacher Zone | FAQs | Contact Us | Login  If you like what you see in Mathguru
Subscribe Today
 For 12 Months US Dollars 12 / Indian Rupees 600 Available in 20 more currencies if you pay with PayPal. Buy Now No questions asked full moneyback guarantee within 7 days of purchase, in case of Visa and Mastercard payment WyzAnt Tutoring

Example:Prove Trigonometric Identity Involving Acute Angles

 Post to:   Explanation:

Trigonometry (from Greek trigōnon "triangle" + metron "measure") is a branch of mathematics that studies triangles and the relationships between their sides and the angles between these sides. Trigonometry defines the trigonometric functions, which describe those relationships and have applicability to cyclical phenomena, such as waves. It has applications in both pure mathematics and applied mathematics, where it is essential in many branches of science and technology.

http://en.wikipedia.org/wiki/Trigonometry

# List of trigonometric identities

In mathematics, trigonometric identities are equalities that involve trigonometric functions and are true for every single value of the occurring variables. Geometrically, these are identities involving certain functions of one or more angles.

These identities are useful whenever expressions involving trigonometric functions need to be simplified. An important application is the integration of non-trigonometric functions: a common technique involves first using the substitution rule with a trigonometric function, and then simplifying the resulting integral with a trigonometric identity.

### Trigonometric functions

The primary trigonometric functions are the sine and cosine of an angle. These are sometimes abbreviated sin (θ) and cos (θ), respectively, where θ is the angle, but the parentheses around the angle are often omitted, e.g., sin θ and cos θ.

The tangent (tan) of an angle is the ratio of the sine to the cosine: Finally, the reciprocal functions secant (sec), cosecant (csc), and cotangent (cot) are the reciprocals of the cosine, sine, and tangent: (Our solved example in mathguru.com uses this concept).

These definitions are sometimes referred to as ratio identities.

## Pythagorean identity

The basic relationship between the sine and the cosine is the Pythagorean trigonometric identity: (Our solved example in mathguru.com uses this concept).

where sin2 θ means (sin (θ))2.

This can be viewed as a version of the Pythagorean Theorem, and follows from the equation x2 + y2 = 1 for the unit circle. This equation can be solved for either the sine or the cosine: http://en.wikipedia.org/wiki/Trigonometry

The above explanation is copied from Wikipedia, the free encyclopedia and is remixed as allowed under the Creative Commons Attribution- ShareAlike 3.0 Unported License.

 © Copyright 2011 - 12 Educomp Solutions Ltd. About Mathguru | Site Map | Contact Us | FAQs | Copyright Info | Terms of Use | Privacy Policy