Inradius, Circumradius, Exradii & Pedal Triangle | Solution of Triangles | JEE Maths

In this lecture, we dive deeper into triangle geometry and trigonometry by studying some extremely important quantities — inradius, circumradius, exradii, and the concept of the pedal triangle. These ideas frequently appear in JEE Main, JEE Advanced, and Olympiad-level problems, especially in questions involving triangle properties, area relations, and geometric transformations. At LimitXToIIT, the goal is to build strong conceptual clarity so that complex problems become intuitive and elegant to solve. 📚 In this lecture you’ll learn: ✔ Meaning and geometric interpretation of inradius (r) ✔ Understanding circumradius (R) and its important relations ✔ Concept of exradii and excircles of a triangle ✔ Important formulas connecting area, semiperimeter and radii ✔ Introduction to the pedal triangle and its geometric significance ✔ Problem-solving insights useful for JEE-level questions Area–Inradius Relation Where 𝑟 r is the inradius and 𝑠 s is the semiperimeter of the triangle.