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:

Drive Pinion

The smaller gear in a gear set that transfers motion to the larger gear or gear rack, frequently used in steering systems and differentials.

Ring Gear

A large gear that interacts with the starter motor's pinion gear to start an engine or as part of the differential in vehicles to power the wheels.

Two-speed Axles

Axle configurations allowing a vehicle to switch between two gear ratios, optimizing performance and fuel efficiency.

Double-reduction

A gear arrangement in transmissions that uses two sets of gears to significantly reduce the input speed, providing increased torque.