Last updated at May 29, 2018 by Teachoo

Transcript

Ex 11.1, 9 Find the centre and radius of the circle 2x2 + 2y2 – x = 0 Given 2x2 + 2y2 – x = 0. We need to make this in form (x – h)2 + (y – k)2 = r2 From (1) 2x2 + 2y2 – x = 0 2x2 + y2− 𝑥2 = 0 x2 + y2 − 𝑥2 = 02 x2 − 𝑥2 + y2 = 0 (x)2 − 2 × 14(x) + y2 = 0 [x2 − 2 × 14x + 142] − 142 + y2 = 0 [x2 − 2 × 14x + 142] − 142 + y2 = 0 Using (a − b)2 = a2 + b2 − 2ab 𝑥−142 − 142 + y2= 0 𝑥−142 + y2 = 142 𝑥−142 + (y − 0)2 = 142 Comparing (2) with (x – h)2 + (y – k)2 = r2 h = 14 , k = 0 & r = 14 Hence center of circle (𝟏𝟒, 0) & Radius of circle = r = 𝟏𝟒

Chapter 11 Class 11 Conic Sections

Serial order wise

About the Author

Davneet Singh

Davneet Singh is a graduate from Indian Institute of Technology, Kanpur. He has been teaching from the past 9 years. He provides courses for Maths and Science at Teachoo.