SOLUTION: find the polar of square root of 3- square root of 3i thank you,

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Question 519337: find the polar of square root of 3- square root of 3i
thank you,

Answer by Edwin McCravy(20059) About Me  (Show Source):
You can put this solution on YOUR website!
3 - sqrt%283%29i

This is the vector from the origin (0,0) to point %28matrix%281%2C3%2C3%2C%22%2C%22%2C-sqrt%283%29%29%29. 
It has length r, which is always a positive number.

So we draw the vector:



Then we draw the perpendicular to the x-axis:




Then the green line is the same as the y-coordinate -sqrt%283%29,
negative because it goes down from the x-axis. and the horizontal
line from the origin to the green line is the x-coordinate 3.




We calculate r which is the length of the vector by the Pythagorean
theorem:

r² = x² + y²

r² = 3² + (-sqrt%283%29)²

r² = 9 + 3

r² = 12

r = sqrt%2812%29

r = sqrt%284%2A3%29

r = 2sqrt%283%29

Next we calculate theta, which is the angle from
the right side of the x-axis to the vector, as indicated
by the red arc below:



First we calculate the reference angle, indicated by the blue arc, the
smallest angle between the vector and the x-axis:



We can calculate it using any trig function, let's pick the sine:

sin(reference angle) = abs%28y%29%2Fr%29 =  

So the reference angle is 30° and therefore theta = 360° - 30° = 330°

So the trig form (or polar form) of the complex number

3 - sqrt%283%29i

is

r(costheta + i·sintheta) or

2sqrt%283%29[cos(330°) + i·sin(330°)]

Edwin