obligatory vs unjustified

obligatory

adj
  • Requiring a matter or obligation. 

  • Imposing obligation, legally, morally, or otherwise; binding; mandatory. 

unjustified

adj
  • Not justified, having no justification, unwarranted. 

  • Not justified (of text, arranged on a page or a computer screen such that the left and right ends of all lines within paragraphs are aligned) 

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