Multiply the Complex Numbers $9 \left( \cos \frac { 7 \pi } { 6 } + i \sin \frac { 7 \pi } { 6 } \right) 4 \left( \cos \frac { 3 \pi } { 7 } + i \sin \frac { 3 \pi } { 7 } \right)$

question 289

Multiple Choice

Multiply the complex numbers.Write the answer in trigonometric form. $9 \left( \cos \frac { 7 \pi } { 6 } + i \sin \frac { 7 \pi } { 6 } \right) 4 \left( \cos \frac { 3 \pi } { 7 } + i \sin \frac { 3 \pi } { 7 } \right)$

• A) \(36 \left( \cos \frac { 67 \pi } { 42 } + i \sin \frac { 67 \pi } { 42 } \right)\)
• B) \(36 \left( \cos \frac { 10 \pi } { 13 } + i \sin \frac { 10 \pi } { 13 } \right)\)
• C) \(36 \left( \cos \frac { \pi } { 2 } + i \sin \frac { \pi } { 2 } \right)\)
• D) \(13 \left( \cos \frac { 67 \pi } { 42 } + i \sin \frac { 67 \pi } { 42 } \right)\)
• E) \(13 \left( \cos \frac { \pi } { 2 } + i \sin \frac { \pi } { 2 } \right)\)

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Definitions:

Polygraphs

Instruments used to measure physiological responses to questions, purportedly to determine truthfulness, often referred to as lie detectors.

Sympathetic Nervous System

A part of the autonomic nervous system that activates the body's fight-or-flight response during perceived threats.

Concealed Information Test

The Concealed Information Test is a psychological assessment tool used to determine if a person has knowledge of information that they are trying to conceal.

Parasympathetic Arousal

The activation of the parasympathetic nervous system, leading to a state of relaxation and recovery after stress or danger.