Polar Coordinates and Complex Numbers

The force on an object is represented by the complex number 8 + 7i, where the components are measured in newtons. What is the magnitude of the force?

• about 15.67 N

• about 1.09 N

• about 56.13 N

• about 10.63 N

Which point represents (2, π/6)

• F

• E

• B

• A

Which point represents (3, 3π/4)?

• F

• E

• B

• A

Find the distance between the two points.

• 
• 
• 
• 

i¹³

• -1

• 1

• i

• -i

what does i ^ 129 =?

• -i

• i

• 1

• -1

Calculate:
(4 − 7i) − (-3 + 6i)

• 7 − 13i

• 7 − i 

• 1 − 13i

• 1 − i 

Calculate (multiply):
 (4 + 3i)(4 − 3i)

• 16 − 9i²

• 25

• 7

• 8 − 6i

Calculate(Divide, multiply by conjugate):

• -3/4 − 1/4i

• 3/4 + 1/4i

• -3/4 + 1/4i

• 3/4 − 1/4i

Which of the following are polar coordinates for point P. There may be more than one answer.

• ( 4, 45°)

• ( 4, -315°)

• ( 4, 225°)

• ( -4, 225°)