How do you convert (0, 9) into polar coordinates?

1 Answer

It turns out that when the argument for the arctangent is undefined, this means that the angle is either #90# degrees or #270# degrees. Because the y coordinate is positive, this means that the angle theta is # 90# degrees.

The radius is #r=sqrt(x^2+y^2)=sqrt(0^2+9^2)=9#

Hence the point #(0,9) # in polar coordinates is # (9,90^o) #.

Remember that when you have a point in cartesian cooridnates
#(x,y)# its polar coordinates are

#(sqrt(x^2+y^2),arctan(y/x))#