How do you convert #r = 3cos(theta)# into cartesian form?

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Answer 1 · 2015-11-22T21:00:49

Use the identities:

#r^2=x^2+y^2#
#x=rcostheta#

First, multiply the equation by r:

#r^2=3(rcostheta)#

Now, substitute the identities:

#x^2+y^2=3x#

#x^2+y^2-3x=0#

A circle with radius 1.5 and center #(1.5,0)#

hope that helped

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