How do you convert the Cartesian coordinates (2√3, 2) to polar coordinates?

1 Answer
Sep 5, 2015

(4,pi/6)(4,π6).

Explanation:

Let (x,y)(x,y) be a coordinate on the Cartesian plane.

The corresponding polar coordinate is (r,theta)(r,θ), where:

r = sqrt(x^2 + y^2) r=x2+y2

(You might notice that this is similar to the distance formula; that's not a coincidence, rr is the distance from the point to the pole (a.k.a. the center) )

and:

theta = tan^-1(y/x)θ=tan1(yx)


So, given (2sqrt(3),2)(23,2):

r = sqrt((2sqrt(3))^2 + 2^2)r=(23)2+22

r = sqrt(12+4)r=12+4

r = sqrt(16)r=16

r = 4r=4

theta = tan^-1(2/(2sqrt(3)))θ=tan1(223)

theta = tan^-1(1/sqrt(3))θ=tan1(13)

theta = tan^-1(sqrt(3)/3)θ=tan1(33)

theta = pi/6θ=π6

We can say that theta = pi/6θ=π6 (and not (5pi)/65π6 , etc.) because xx and yy are both positive, which means the point is in the first quadrant.

Thus, the point in polar coordinates is (4,pi/6)(4,π6).