Matlab - Ayuda por favor con estos ejercicios.. no me salen.

>> raiz_n_esima

n =

     5

z =

a + b*1i

z =

25 - 15^(1/2)*1i

a =

25

b =

-15^(1/2)

r =

8*10^(1/2)

alpha =

-atan(15^(1/2)/25)

k =

     0

     1

     2

     3

     4

wk =

                       (cos(atan(15^(1/2)/25)/5) - sin(atan(15^(1/2)/25)/5)*1i)*(8*10^(1/2))^(1/5)

 (sin((2*pi)/5 - atan(15^(1/2)/25)/5)*1i + cos((2*pi)/5 - atan(15^(1/2)/25)/5))*(8*10^(1/2))^(1/5)

 (sin((4*pi)/5 - atan(15^(1/2)/25)/5)*1i + cos((4*pi)/5 - atan(15^(1/2)/25)/5))*(8*10^(1/2))^(1/5)

 (sin((6*pi)/5 - atan(15^(1/2)/25)/5)*1i + cos((6*pi)/5 - atan(15^(1/2)/25)/5))*(8*10^(1/2))^(1/5)

 (sin((8*pi)/5 - atan(15^(1/2)/25)/5)*1i + cos((8*pi)/5 - atan(15^(1/2)/25)/5))*(8*10^(1/2))^(1/5)