Write the Word or Phrase That Best Completes Each Statement $$\cos ( x - y ) - \cos ( x + y ) = 2 \sin x \sin y$$

question 106

Essay

Write the word or phrase that best completes each statement or answers the question.
Establish the identity.
- $$\cos ( x - y ) - \cos ( x + y ) = 2 \sin x \sin y$$

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Definitions:

Surgical Site Infection

An infection that occurs after surgery in the part of the body where the surgery took place, often causing complications.

Microorganism

A microscopic organism, such as a bacterium, virus, or fungus, that can be pathogenic or beneficial in nature.

Surgical Asepsis

The elimination of all microorganisms from objects or working areas; also called sterile technique.

Biological Sterilization Indicator

Devices that contain microorganisms of known resistance to a particular sterilization process, used to verify the effectiveness of the process.