The polar curve r=3cos2θ is traced for 0≤θ≤2π.
(a) Find the Cartesian coordinates of the point on the curve that corresponds to θ=8π.
(b) Compute the slope dxdy of the curve at θ=8π.
(c) Express the equation of the tangent line at that point in the implicit linear form Ax+By=C, where A, B, and C are simplified exact values.