Question

help anyone please? really need it

Answer 1

Answer:

Step-by-step explanation:

Answer 2

Answer:

z₁ = 20 exp ( 7 π i / 6 )  =  20 cis ( 7 π / 6)

(use whichever notation you've been using in class!)

Step-by-step explanation:

|z₁| = 10 × |-√3 - i| = 10 × √(3 + 1) = 10√4 = 10×2 = 20

arctan (-10 / -10√3) = arctan (1/√3) = π/6

As real and imaginary parts are negative, z₁ is in the third quadrant, so

arg(z₁) = π + π/6 = 7π/6

So...

z₁ = 20 exp ( 7 π i / 6 )  =  20 cis ( 7 π / 6)