instructive vs pedagogical

instructive

adj
  • Conveying knowledge, information or instruction. 

noun
  • A case in the Finnish and Estonian languages. It expresses the means or the instrument used to perform an action. 

pedagogical

adj
  • Of, or relating to pedagogy; teaching. 

  • Haughty and formal. 

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