/sci/ - Science & Math

I'm considering quitting mathematics. I was planning on going to grad school this autumn, but honestly, I don't know if I have what it takes. My math skills aren't that great, and I feel like my undergraduate education has been very shaky. My university had a very poor math department and as such my curriculum lacked anything on algebra, functional analysis, or geometry. So I had to learn these topics more or less on my own.

Where do I begin if I want to learn about human health and how to improve it?

They don't spin, they twirl

How do noise cancelling headphones work and why can't i steer a beam of noise cancelling at my neightbours yard yet?