unfold vs work out

unfold

verb
  • To reveal. 

  • To undo a folding. 

  • To release from a fold or pen. 

  • To turn out; to happen; to develop. 

  • To open (anything covered or closed); to lay open to view or contemplation; to bring out in all the details, or by successive development. 

noun
  • In functional programming, a kind of higher-order function that is the opposite of a fold. 

work out

verb
  • To make sense of. 

  • To strengthen a part one’s body by exercise. 

  • To earn a wage working away from one's farm. 

  • To bring about or cause to happen by work or effort. 

  • To succeed; to result in a satisfactory situation. 

  • To conclude with the correct solution. 

  • To remove all the mineral that can be profitably exploited. 

  • To smooth or perfect. 

  • To exercise, especially by lifting weights. 

  • Used other than figuratively or idiomatically: see work, out. 

  • To calculate. 

How often have the words unfold and work out occurred in a corpus of books? (source: Google Ngram Viewer )