Concepts in complex numbers

Express the complex number in trigonometric (polar) form.

-2 + 5i

How can you identify a complex unit in a graph?

• By seeing if it is in cartesian coordinate and Y-axis number has an "i"

• By seeing if it is in polar coordinate and Y-axis number has an "i"

• By asking to your teacher the right answer

Identify the graph for the polar equation r=4 sinθ

• 
• 
• 
• 

Which point represents (5, π)

• F
• E
• B
• A

Express the point in trig form in standard form.
4 ( cos π /3 + i sin π /3)

• 2 + 2√3 i
• 2 + √3 i
• 2 - 2√3 i
• -2 + 2√3 i

If you are multiplying complex numbers, which form should they be in?

• Rectangular

• Polar

• Either One is Fine

Write 16i in polar form

• $16cis0$

• $16cis\pi$

• $16cis\ \frac{\pi}{2}$

• $16icis\pi$

Write the complex number in polar form

• 3 ( cos 3π/2 + i sin 3π/2)
• 3 ( cos π/2 + i sin π/2)
• 9 ( cos 3π/2 + i sin 3π/2)
• 3 ( cos 2π + i 2π)

Write the complex number in Polar Form. Express the argument in Degrees:    6+0i

•  $6\left(\cos\ 270\degree\ +\ i\ \sin\ 270\degree\right)$  

•  $6\left(\cos\ 180\degree\ +\ i\ \sin\ 180\degree\right)$  

•  $6\left(\cos\ 0\degree\ +\ i\ \sin\ 0\degree\right)$  

•  $6\left(\cos\ 90\degree\ +i\ \sin\ 90\degree\right)$  

Which of the following is the equation of a straight line that passes through quadrants 2 and 4?