The following is a question from a textbook for one of my university classes called computational logic. The class is actually being offered as a philosophy class and since I have no real mathematical background I don't really know how to proceed. any help would be appreciated.
"Show that the set of real numbers is equinumerous with the the set of points on a semicircle from a circle with a diameter of 1."
EDIT: I can now add that the semicircle given in the diagram that accompanied the question is the bottom half of the circle described by $0.25=(x-0.5)^2+(y-0.5)^2$. though I dont know if that really matters.