Are there any definitions of functions like sqrt(), sin(), cos(), tan(), log(), exp() (these fr
Every implementation may be different, but you can check out one implementation from glibc's (the GNU C library) source code.
edit: Google Code Search has been taken offline, so the old link I had goes nowhere.
The sources for glibc's math library are located here:
http://sourceware.org/git/?p=glibc.git;a=tree;f=math;h=3d5233a292f12cd9e9b9c67c3a114c64564d72ab;hb=HEAD