Discover Questions

If r=a√(1- cos x), show that (dr/dx)=(a/√2) cos(x/2)? How long before my test do I take the frist pills and how long to take the next two? Factorise completely
4a9+a how do are work this out ,I know you use the difference of two cubes? Hmm! To be, or not to be? That is the question!? Can cloning humans from plucked out hair follicles be done?