Posted by **Lucy** on Tuesday, September 30, 2008 at 3:45pm.

I am having difficulty with two problems:

1) Evaluate (1+i)^12 by using DeMoivre's Theorem. Express the result in rectangular form.

So far I have: r=sqrt(1)^2+(1)^2 which simplified is sqrt2. Don't know how to proceed.

2) Write the polar equation theta = 45 degrees in rectangular form.

I don't even know how to proceed to do this.

Any help would be great!

- Pre-calculus -
**bobpursley**, Tuesday, September 30, 2008 at 4:02pm
(1+i)^12 is sqrt2 @ 45 to the 12th power, or sqrt2 ^12 @45x12

1@45 is .707i + .707j where i,j are unit vectors in the x,y directions.

- Pre-calculus -
**Kate**, Wednesday, May 6, 2009 at 8:42pm
x = r cos(45) ...(1)

y = r sin(45) ...(2)

Dividing (2) by (1):

y / x = tan(45) = 1

y = x.

- Pre-calculus -
**lily**, Thursday, July 9, 2009 at 2:43pm
find the distance between points at (6,-3) and (-1,4). The answer I got was 9.9 and it was wrong.

please help!

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