## How to Applying Quadratics to the Real World

Quadratic functions are wonderful models for many situations that occur in the real world. You can see them at work in financial and physical applications, just to name a couple. This section provides a few applications for you to...

## The function of a half angle of trigonometric

Just as there are identities to find the function values of 2A, there are identities to find cos ½ A, sin ½ A , and tan ½ A. We often call the identities used to find the function values...

## The function of double – angle (2A) of trigonometric

The identities for sin (A + B), cos (A + B), and tan (A + B) are true when A = B. These identities can be used to find the function values of 2A. We often call the identities...

## How to determine of tangent (A – B) and tangent (A + B)

We can use the identity and the identities for sin (A + B) and cos (A + B) to write identities for tan (A + B) and tan (A – B). Tangent of (A + B) We would like...

## Determine sine ( A – B) and sine ( A + B) of trigonometric

We can use the cofunction identity sin =cos (90° – ) and the identities for cos (A – B) and cos (A + B) to derive identities for sin (A – B) and sin (A + B). Sine of...

## Cosine of sum for trigonometric or cosine (A + B)

We know that cos (A + B) can be written as cos (A – (-B)). Therefore, cos (A + B) = cos (A – (-B)) = cos A cos (-B) + sin A sin (-B) We would like to...