Grade 11AlgebraThe ex – radii r1, r2, r3 of ∆ ABC are in H. P. Show that its sides a, b, c are in A. P. Simran Bhatia 12 Years agoGrade 11
Aditi Chauhan12 Years ago Hello Student, Please find the answer to your question KEY CONCEPT: Ex – radii of a ∆ABC are r1 = ∆/s – a, r2 = ∆/s – b r3 = ∆/s – c As r1, r2, r3 are in H. P. ∴ 1/r1, 1/r2, 1/r3 are in AP ⇒ s – a/∆, s – b/∆, s – c/∆ are in AP ⇒ s – a, s – b, s – c are in AP ⇒ -a, -b, -c are in AP. ⇒ a, b, c are in A. P. ThanksAditi ChauhanaskIITians Faculty