Establish the Identity $$\cot ^ { 2 } x = ( \csc x - 1 ) ( \csc x + 1 )$$

question 81

Essay

Establish the identity.
- $$\cot ^ { 2 } x = ( \csc x - 1 ) ( \csc x + 1 )$$

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Definitions:

Permeability Barriers

Structures or partitions that prevent or regulate the passage of substances across them, often referring to skin, mucous membranes, or cell membranes.

Proteins

Essential molecules composed of amino acids that assist in various bodily functions, including catalysis of metabolic reactions, DNA replication, and response to stimuli.

Pericapillary Cells

Cells located around capillaries, often referring to pericytes, which play roles in vascular stability, blood flow regulation, and angiogenesis.

Macrophages

Immune system cells responsible for detecting, engulfing, and destroying pathogens and apoptotic cells.