explain TR TC APPROACH ????
Follow the link below to find the answer to your question. Thereafter, select Chapter-4 'The Theory of The Firm Under Perfect Competition' and after that surf to lesson-3 'Profit Maximisation Conditions for Perfect Competition'. Scroll down to find the topics of 'TR-TC Approach'.
https://www.meritnation.com/cbse/class12-commerce/studymaterial/economics/introductory-microeconomics/1_15_16_338
Keep posting!!
https://www.meritnation.com/cbse/class12-commerce/studymaterial/economics/introductory-microeconomics/1_15_16_338
Keep posting!!