+845 Find the intersection between graph r=1 and r=2cosθ
i did cosθ= 1/2
cos^-1 1/2 = 1/3π (radiance)
from here on ward i was told to add something to this which should give me 5/3π
and thus my 2 intersection should be
(1, 1/3π) (1, 5/3π)
please tell me what i do in order to get to 5/3π
+129852 Set the r's equal and we have that
2cos θ = 1 divide both sides by 2
cos θ = 1/2
arccos (1/2) = θ
Remember that arccos has a range of [-pi,2, pi/2 ]
Note that this happens at pi/3 and at -pi/3 = 5pi/3 if we are on the interval [0, 2pi ]
So...the intersection points are
(r, θ) = ( 1, pi/3) and (1, 5pi/3 )
