behaiour of AR, MR in monopoly and monopolistic market ?

Monopoly and monopolistic markets are both a form of imperfect competitive markets. Thus, the relationship between AR and MR in monopoly and monopolistic market can be understood by studying the relationship between AR and MR under imperfect competition. This relationship has been explicitly covered in our study material. You can find it in Microeconomics- The Theory of The Firm under Perfect Competition (Lesson- 1) under the heading of 'Relationship between TR, AR and MR- Under Imperfect Competition Market' of our study material.