co- vs syn-

co-

prefix
  • together; mutually; jointly 

  • to the same degree 

  • partner or subordinate in an activity 

  • of the opposite, of the counterpart; dual 

syn-

prefix
  • with, together 

  • identical 

  • concomitant 

How often have the words co- and syn- occurred in a corpus of books? (source: Google Ngram Viewer )