Combining Two Manipulated Plots Dependent on Same Variables

Question

I need to combine two plots on the same graph to highlight the intersection of the two while being able to manipulate various parameters that are common to both functions. I need to have the slider simultaneously change the parameters for each function and continue to plot on the same graph. Here's my code:

Manipulate[
 right = Plot[Cos[2*Pi*b*n/\[Lambda]], {n, 0, 2}], {{a, 25, 
   "x-separation"}, 20, 30}, {{b, 25, "z-separation"}, 20, 
  30}, {{r, 1, "Rod Radius"}, .1, 
  10}, {{\[Lambda], 100, "Wavelength"}, 50, 200}]

Manipulate[
 left = Plot[
   Cos[2*Pi*
      b/\[Lambda]] + (\[Lambda]*Sin[2*Pi*b/\[Lambda]])/(2 a*
       Log[a/(2*Pi*r)]), {n, 0, 2}], {{a, 25, "x-separation"}, 20, 
  30}, {{b, 25, "z-separation"}, 20, 30}, {{r, 1, "Rod Radius"}, .1, 
  10}, {{\[Lambda], 100, "Wavelength"}, 50, 200}]

Show[right, left] // Dynamic

Any help is much appreciated!

Answer 1

Manipulate[
 Plot[{Cos[2*Pi*b/λ] + (λ*Sin[2*Pi*b/λ])/(2 a*Log[a/(2*Pi*r)]), 
       Cos[2*Pi*b*n/λ]}, {n, 0, 2}], 
{{a, 25, "x-separation"}, 20, 30}, {{b, 25, "z-separation"}, 20, 30}, 
{{r, 1, "Rod Radius"}, .1, 10}, {{λ, 100, "Wavelength"}, 50, 200}]

Answer 2

Here is another simpler example that can compare how amplitude, frequency, and phase shift can impact the shape of a Sine function.

Manipulate[
Plot[{Sin[x], a Sin[k x + phi]}, {x, 0, 2 Pi}],
{k, .1, 4},{a, 1, 2}, {phi, 0, 2 Pi}
 ]