### Home > PC > Chapter 11 > Lesson 11.2.2 > Problem 11-87

11-87.

Show that *i ^{n} *can be written as cos(

*i*sin(

Recall from problem 11-85 that *i* can be written as:

Now use DeMoivre's theorem to write *i ^{n}*.

11-87.

Show that *i ^{n} *can be written as cos(

Recall from problem 11-85 that *i* can be written as:

Now use DeMoivre's theorem to write *i ^{n}*.