JEE Main 2017MathematicsCircleMediumMCQ

JEE Main 2017 — Circle Question with Solution

JEE Main 2017 (02 Apr)

Question

The radius of a circle, having minimum area, which touches the curve y=4-x2 and the lines, y=x is:

Choose an option

Show full solutionCorrect option: C
Correct answer
C42-1

Step-by-step explanation

Length of perpendicular from centre of circle to tangent line r=k2

 And r=4-k 



⇒  r=4-k=k2

⇒4=k+2k2

⇒ k=422+1

⇒r=422+12

⇒r=42+1 

⇒   r=42-1

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About this question

This is a previous-year question from JEE Main 2017, covering the Circle chapter of Mathematics. PrepSharp catalogues every PYQ from JEE Main with a verified answer key and step-by-step solution prepared by IIT alumni — so you can search by chapter, topic or year and revise efficiently.