Find the Trigonometric Form of - 21 - 21i $\frac { 21 } { 2 } \left( \cos \frac { 5 \pi } { 2 } + i \sin \frac { 5 \pi } { 2 } \right)$

question 5

Multiple Choice

Find the trigonometric form of - 21 - 21i. ​

• A) \(\frac { 21 } { 2 } \left( \cos \frac { 5 \pi } { 2 } + i \sin \frac { 5 \pi } { 2 } \right)\)
• B)​ \(21 \left( \cos \frac { 5 \pi } { 2 } + i \sin \frac { 5 \pi } { 2 } \right)\)
• C)​ \(21 \left( \cos \frac { 5 \pi } { 4 } + i \sin \frac { 5 \pi } { 4 } \right)\)
• D)​ \(21 \sqrt { 2 } \left( \cos \frac { 5 \pi } { 4 } + i \sin \frac { 5 \pi } { 4 } \right)\)
• E)​ \(\frac { 441 } { 4 } \left( \cos \frac { 5 \pi } { 8 } + i \sin \frac { 5 \pi } { 8 } \right)\)

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Definitions:

Neural Tube Defect

A type of birth defect affecting the brain, spine, or spinal cord, occurring in the early stages of pregnancy due to the neural tube not closing completely.

Folic Acid

A form of vitamin B9 that is essential for the production of healthy red blood cells and is particularly important during periods of rapid growth such as pregnancy.

Supplement

A product taken orally that contains one or more ingredients (such as vitamins or amino acids) that are intended to supplement one's diet and are not considered food.

Neural Tube Defects

Birth defects of the brain, spine, or spinal cord that occur when the neural tube does not close completely during early fetal development.