Q.

A line segment AB of length λ moves such that the points A and B remain on the periphery of a circle of radius λ. Then the locus of the point that divides the line segment AB in the ratio 2 : 3, is a circle of radius             [2023]

1 195λ      
2 23λ      
3 197λ      
4 35λ  

Ans.

(1)

OAP=60°                          [ OA=OB=AB=λ]

AP=2λ5  (Given)

cos60°=OA2+AP2-OP22·OA·AP

12=λ2+4λ225-OP22λ·2λ5

2λ25=29λ225-OP2OP2=2925λ2-25λ2=1925λ2

Required locus is x2+y2=1925λ2

   Radius=195λ