Question

Find the point(s) of intersection for the polar curves with equations r = 6 cos θ and r = 4 − 2 cos θ. (10 points)

A) pi over 6 and negative pi over 6
B) pi over 3 and negative pi over 3
C) pi over 2 and negative pi over 2
D) 0, π

Answer 1

just plug and chug
6 cosθ = 4 - 2cosθ
6cosθ = 6
cosθ = 1
so, what do you think?

Answer 2

I got 0, pi, is this right? I got this because cos 0 = 1 and cos pi = -1

Answer 3

but we want cosθ = 1, not -1.

Answer 4

I think you made a mistake
6 cosθ = 4 - 2cosθ
You wrote: 6cosθ = 6
But, 6 cos theta = 4 - 2cos theta is equal to 8 cos theta = 4
which means cos theta = 4/8 0r cos theta = 1/2
Please check if I am right or if I made a mistake somewhere

Answer 5

You are correct; Good catch. I got my 2's and 4's mixed up ...