Verify That the Equation Is an Identity $$\sin ( x + y ) - \sin ( x - y ) = 2 \cos x \sin y$$

question 54

Essay

Verify that the equation is an identity.
- $$\sin ( x + y ) - \sin ( x - y ) = 2 \cos x \sin y$$

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Definitions:

Dense Connective Tissue

A type of connective tissue with closely packed collagen fibers, providing strength and stiffness to structures like tendons and ligaments.

Fibrous Synarthroses

A type of joint characterized by fibrous tissue connecting bones, which allows minimal to no movement.

Cartilaginous Synarthroses

Joints that are connected entirely by cartilage, allowing for very limited movement, such as the intervertebral discs in the spine.

Synovial Joints

Highly movable joints that are enclosed within a synovial capsule, producing a fluid that lubricates the joint to reduce friction.