inexact vs on the wrong track

inexact

adj
  • having a path-dependent integral 

  • Imperfectly conforming; exceeding or falling short in some respect. 

  • Imprecisely or indefinitely conceived or stated. 

on the wrong track

prep
  • using the wrong general approach to a particular task or problem; pursuing something in an unpromising way 

How often have the words inexact and on the wrong track occurred in a corpus of books? (source: Google Ngram Viewer )