What is the trigonometric form of (-6-5i) ?

1 Answer
Jun 14, 2018

color(gray)((-6 - i 5) = (7.81 cos (219.8) + i 7.81 sin (219.8))

Explanation:

z = (-6 - i 5)

Polar form (r, theta)

r = |sqrt((-6)^2 + (-5)^2| = |sqrt61 | = 7.81

theta = arctan (-5/-6) = arctan (5/6) = 180 + 39.8^@ = 219.8^@, " III Quadrant"

Trigonometric form of z = (rcos theta + i r sin theta)

color(gray)((-6 - i 5) = (7.81 cos (219.8) + i 7.81 sin (219.8))