Write the Complex Number in Rectangular Form $9 \left( \cos 180 ^ { \circ } + i \sin 180 ^ { \circ } \right)$

question 150

Multiple Choice

Write the complex number in rectangular form.
- $9 \left( \cos 180 ^ { \circ } + i \sin 180 ^ { \circ } \right)$

• A) 9
• B) \(- 9 \mathrm { i }\)
• C) \(9 \mathrm { i }\)
• D) \(- 9\)

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Definitions:

Lewis Structure

A diagrammatic representation of the bonding between atoms of a molecule and the lone pairs of electrons in the molecule, showing how valence electrons are distributed.

Oxygen Molecule

A diatomic molecule composed of two oxygen atoms (O2), essential for aerobic respiration in animals.

Resonance Structure

Different forms of a molecule where the chemical connectivity is the same but the electrons are distributed differently around the structure.

Ammonia Molecule

A compound composed of one nitrogen atom and three hydrogen atoms (NH3), notable for its sharp odor.