Trigonometric Form of a Complex Number...1

[nycmathguy]

Section 6.6

 

[MathLover1]

you got r=2sqrt(5) and θ= -π/4, that was enough to do

z=r(cos(θ)+i*sin(θ))

answer is: z=2sqrt(5)(cos(-π/4)+i*sin(-π/4))

 

[nycmathguy]

you got r=2sqrt(5) and θ= -π/4, that was enough to do

z=r(cos(θ)+i*sin(θ))

answer is: z=2sqrt(5)(cos(-π/4)+i*sin(-π/4))

Ok. I tried. Thanks for the correction.

 

[nycmathguy]

you got r=2sqrt(5) and θ= -π/4, that was enough to do

z=r(cos(θ)+i*sin(θ))

answer is: z=2sqrt(5)(cos(-π/4)+i*sin(-π/4))

Are you sure that r = 2•sqrt{5}? I think r = 5•sqrt{2}.
You say?