Solve the Equation in the Interval [0°, 360°) $2 \cos ^ { 3 } \theta = \cos \theta$

question 132

Multiple Choice

Solve the equation in the interval [0°, 360°) . Give solutions to the nearest tenth, if necessary.
- $2 \cos ^ { 3 } \theta = \cos \theta$

• A) \(\left\{ 45 ^ { \circ } , 135 ^ { \circ } , 225 ^ { \circ } , 315 ^ { \circ } \right\}\)
• B) \(\left\{ 90 ^ { \circ } , 270 ^ { \circ } \right\}\)
• C) \(\left\{ 45 ^ { \circ } , 90 ^ { \circ } , 135 ^ { \circ } , 225 ^ { \circ } , 270 ^ { \circ } , 315 ^ { \circ } \right\}\)
• D) \(\varnothing\)

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Definitions:

Hemolysis

Destruction of red blood cells in such a manner that hemoglobin is released.

Erythrocyte

Red blood cell; biconcave disk containing hemoglobin.

Reticulocyte

Young red blood cell with a network of basophilic endoplasmic reticulum occurring in larger numbers during the process of active red blood cell synthesis.

Immature Red Blood Cell

A young red blood cell that is still developing and has not yet reached its fully mature form, capable of carrying oxygen efficiently.