Question

Express 2 (cos pi/3 + i sin pi/3) in rectangular form.

-1 + sqrt 3i
1 + sqrt 3i
1 - sqrt 3i
Sqrt 3 +i

Answer 1

distribute
then evaluate cos(pi/3) and sin(pi/3)

Answer 2

How?

Answer 3

do you have the unit circle handy?

Answer 4

No, I don't.

Answer 5

you can look up unit circle
https://www.google.com/url?sa=i&rct=j&q=&esrc=s&source=images&cd=&cad=rja&uact=8&ved=0ahUKEwiu7PTwqunLAhXsvYMKHQOACQYQjRwIAw&url=https%3A%2F%2Fwww.mathsisfun.com%2Fgeometry%2Funit-circle.html&psig=AFQjCNHBHl5nQ3Jt_hMKIwJUGpTw7ljesw&ust=1459459078841159

Answer 6

you should see pi/3 there in the first quadrant

Answer 7

the ordered pair gives (cos(pi/3),sin(pi/3))

Answer 8

Thanks

Answer 9

so cos(pi/3)=?
and sin(pi/3)=?