Use the Sum-To-Product Formulas to Find the Exact Value of the Given

question 24

Multiple Choice

Use the sum-to-product formulas to find the exact value of the given expression.
$\cos 150 ^ { \circ } + \cos 30 ^ { \circ }$

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Definitions:

Chorionic Villi

Finger-like projections from the chorion that extend into the uterine wall, facilitating nutrient exchange between mother and fetus.

Syncytiotrophoblast

Outer layer of the trophoblast composed of multinucleated cells.

Amniotic Cavity

A fluid-filled sac that encloses and protects the developing fetus in the uterus.

Endoderm

The innermost layer of cells or tissue of an embryo in early development, which gives rise to the lining of the digestive and respiratory systems.