Alpine is built using musl-libc. Software compiled against the more common glibc will often not run in this environment because it can’t find the expected dynamic loader.
Common ways to solve this include either (a) compile the code yourself or (b) install a version that has been built elsewhere for Alpine. I don’t believe either of these is going to be an option for Rar.
Your best bet is just to replace Alpine as your base image with something (really, almost anything) else (debian, ubuntu, fedora, centos, etc).
(Note that if you just need to extract Rar archives, you can simply apk install unrar under Alpine).
CLICK HERE to find out more related problems solutions.