Recent content by rjb

I agree with this 100%. Like the originator, I was self taught at first and struggled with analysis in general and Spivak in particular. Later, on going to university as a very mature student to do mathematical physics, I found it necessary to study from "how to do" books at first whereas Spivak...

A function is a mapping from one [1st] set to another [2nd] which may be equivalent (equal) to the 1st (eg y=x^2, x,y real number - a mapping "within" the set of real numbers. The elements of the sets may be numbers (scalars), vectors, other functions (a function of a function), matrices and so...