Operations with Complex Numbers in Polar Form

Project ID: 
7200000042
Accepted: 
Type: 
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Question: 
Let $a$, $b$, and $c$ be complex numbers, where: $$\begin{aligned} a &= 4\left(\cos \frac{7\pi}{6} + \mathrm{i} \sin \frac{7\pi}{6}\right),\cr b &= \cos \frac{5\pi}{6} + \mathrm{i} \sin \frac{5\pi}{6},\cr c &= 2\left(\cos \frac{2\pi}{3} + \mathrm{i} \sin \frac{2\pi}{3}\right).\ \end{aligned}$$ Match the given complex expressions with their corresponding values expressed in polar form.
Questions Title: 
Expression with complex numbers
Answers Title: 
Value in polar form
Question 1: 
$$\frac{a}{b}$$
Answer 1: 
$$4\left(\cos \frac{\pi}{3} + \mathrm{i} \sin \frac{\pi}{3}\right)$$
Question 2: 
$$c^2$$
Answer 2: 
$$4\left(\cos \frac{4\pi}{3} + \mathrm{i} \sin \frac{4\pi}{3}\right)$$
Question 3: 
$$b\cdot c$$
Answer 3: 
$$2\left(\cos \frac{3\pi}{2} + \mathrm{i} \sin \frac{3\pi}{2}\right)$$
Question 4: 
$$\frac{a\cdot c}{b}$$
Answer 4: 
$$8\left(\cos \pi + \mathrm{i} \sin \pi\right)$$
Question 5: 
$$\left(\frac{a\cdot b}{c}\right)^2$$
Answer 5: 

$$4\left(\cos \frac{2\pi}{3}  + \mathrm{i} \sin \frac{2\pi}{3}\right)$$

Question 6: 
$$\frac{a^3\cdot b}{c^4}$$
Answer 6: 
$$4\left(\cos \frac{5\pi}{3} + \mathrm{i} \sin \frac{5\pi}{3}\right)$$
Answer 7: 
$$2\left(\cos \frac{4\pi}{3} + \mathrm{i} \sin \frac{4\pi}{3}\right)$$
Answer 8: 
$$8\left(\cos \frac{2\pi}{3} + \mathrm{i} \sin \frac{2\pi}{3}\right)$$