purposeful vs unrelenting

purposeful

adj
  • Having a purpose in mind; resolute; determined. 

  • Having purpose; intentional. 

unrelenting

adj
  • Having no pity; not being or becoming lenient, mild, gentle, or merciful 

  • Not relenting; not yielding in strength, severity, or determination. 

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