I'm not sure whether it is integral or Malus law itself I have trouble with. I watched a few YouTube videos and I kind of understand what they are saying, but it doesn't explain it in terms how I visualize it in my head.
Say we have 36 photons, each polarized at 10 degrees more than previous one: 0, 10, 20, 30... 330, 340, and 350 degrees. I'm not sure whether 0 and 180, or 90 and 270 degree polarization is the same, but it doesn't really matter.
Now we pass them all through vertical polarizer, and I conclude only two of those 36 photons should pass, 0 and 180 degree ones. What am I missing?