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polar co ordinates

Hi i keep gettin the wrong answer for this question could someone help me

find the cartesian equation of r=1+sin 2x in the form

(x^2 + y^2)^m =(x+y)^n

thanks alot

Reply 1

dvs

r^2 = x^2 + y^2
sin(t) = y/r
cos(t) = x/r

So:
r = 1 + sin(2t) = 1 + 2sin(t)cos(t)
=> r = 1 + 2(xy/r^2)
=> r^3 = r^2 + 2xy
=> (x^2 + y^2)^3 = x^2 + y^2 + 2xy = (x + y)^2

By the way, next time make sure you post your working. :smile:

Reply 2

Gaz031

sarah12345

Hi i keep gettin the wrong answer for this question could someone help me

find the cartesian equation of r=1+sin 2x in the form

(x^2 + y^2)^m =(x+y)^n

thanks alot