Find the Exact Value $\cos 75 ^ { \circ } \cos 15 ^ { \circ } + \sin 75 ^ { \circ } \sin 15 ^ { \circ }$

question 81

Essay

Find the exact value. $\cos 75 ^ { \circ } \cos 15 ^ { \circ } + \sin 75 ^ { \circ } \sin 15 ^ { \circ }$

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Definitions:

Biological Molecule

Compounds that are vital for the existence and function of living organisms, including proteins, carbohydrates, lipids, and nucleic acids.

Condensation

Chemical reaction in which a large molecule is assembled from smaller sub-units; water also forms.

Polymers

Large molecules composed of many repeated subunits, which can be found in various natural and synthetic materials like plastics, proteins, and DNA.

Monomers

Simple molecules that can join together to form polymers, which are large, complex structures.