To divide (4 - i) / (7 + 2i)4−i7+2i using trigonometric form.
z_1 = (4 - i), z_2 = (7 + 2i)z1=(4−i),z2=(7+2i)
#r_1 = sqrt(4^2 + 1^2) = sqrt 17
r_2 = sqrt(7^2 + -2^2) = sqrt53r2=√72+−22=√53
theta_1 = arctan (-1/4) = 345.96^@, " IV quadrant"θ1=arctan(−14)=345.96∘, IV quadrant
Theta_2 = arctan(2/7) = 15.95^@, " 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(17/53) * (cos (345.96 - 15.95 ) + i sin (345.96 - 15.95 ))
z_1 / z_2 = 0.5664 * (cos (-330.01) + i sin (-330.01))
color(violet)((4 -i) / (7 + 2i) ~~ 0.4905 + i 0.2831