Use a graphing utility to represent the complex number in standard form.Round your answer to 4 decimal places. $9 \left( \cos 62 ^ { \circ } + i \sin 62 ^ { \circ } \right)$
A)7.9465 + 4.2252i
B)4.2252 + 7.9465i
C)4.2252 - 7.9465i
D)7.9465 - 4.2252i
E)None of the above

Question

Use a graphing utility to represent the complex number in standard form.Round your answer to 4 decimal places.  $9 \left( \cos 62 ^ { \circ } + i \sin 62 ^ { \circ } \right)$  
A)7.9465 + 4.2252i
B)4.2252 + 7.9465i
C)4.2252 - 7.9465i
D)7.9465 - 4.2252i
E)None of the above

Quizplus · Accepted Answer

The complex number is in polar form $r(\cos \theta + i\sin \theta)$, where $r = 9$ and $\theta = 62^\circ$. To convert it to standard form $a + bi$, calculate $a = r\cos\theta$ and $b = r\sin\theta$. Using a calculator, $a = 9\cos(62^\circ) \approx 4.2252$ and $b = 9\sin(62^\circ) \approx 7.9465$, so the complex number in standard form is approximately $4.2252 + 7.9465i$.

Use a Graphing Utility to Represent the Complex Number in Standard