How do you convert #x=2# into polar form?

1 Answer
Jul 29, 2016

I found: #r=2/cos(theta)#

Explanation:

Consider the "conversion" diagram between Cartesian and Polar:
enter image source here

#"POLAR"->"CARTESIAN"#
You can see that from Pythagoras: #r=sqrt(x^2+y^2)# and from Trigonometry: #theta=arctan(y/x)#.

OR

#"CARTESIAN"->"POLAR"#
From rigonometry:
#x=rcos(theta)#
#y=rsin(theta)#

Let us consider our expression:
#x=2#
let us use our second transformation formulas in the form: #x=rcos(theta)#
to get:
#rcos(theta)=2#
and:
#r=2/cos(theta)#