How do you divide ( 3i-2) / (i +4 )3i2i+4 in trigonometric form?

1 Answer
Jul 8, 2018

color(maroon)((-2 + 3 i) / (4 + i) ~~ -0.2931 - i 0.82312+3i4+i0.2931i0.8231

Explanation:

To divide (-2 + 3 i) / (4 + i)2+3i4+i using trigonometric form.

z_1 = (-2 + 3 i), z_2 = (4 + i)z1=(2+3i),z2=(4+i)

#r_1 = sqrt(-2^2 + 3^2) = sqrt 13

r_2 = sqrt(4^2 + 1^2) = sqrt 17r2=42+12=17

theta_1 = arctan (-2/3) = 146.31^@, " II quadrant"θ1=arctan(23)=146.31, II quadrant

Theta_2 = arctan(4/1) = 75.96^@, " I quadrant"

z_1 / z_2 = (r_1 / r_2) * (cos (theta_1 - theta_2) + i sin (theta_1 - theta_2))

z_1 / z_2 = sqrt(13/17) * (cos (146.31 - 75.96 ) + i sin (146.31 - 75.96 ))

z_1 / z_2 = sqrt(13/17) * (cos (70.41) + i sin (70.41))

color(maroon)((-2 + 3 i) / (4 + i) ~~ -0.2931 - i 0.8231