Express 5-2i in polar form. Express your answer in radians to the nearest hundreth.

Question

r=sqrt5^2+-2i^2 which equals sqrt21.Arctan of -2/5+pi equals -18.7

Polar form=sqrt21 cis -18.7

Is this correct??

Answer 1

not quite
if x+iy = r e^iT = r (cos T i sin T)
then
r = sqrt (x^2+y^2)
not sqrt [x^2 + (iy)^2]
so r = sqrt (29), not 21