Doubt from locus problems


@Kamalesh_V @Vatsalya @Seshank @bhanu @Pratik @doubtion @pratyaksh_tyagi

my eqn of locus is coming his (x-1)^2/4 +y^2/3=1??

Please send the working

Is it B,D

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Let centre be (h,k).

  1. distance of (h,k) from (0,0) = 5-(radius of circle ®)
  2. Distance of (h,k) from (2,0) = r+1
    Solve them
    I’m getting (x-1)²/9 + y²/8 =1
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Got it

@Sarvesh_Pnchl please try the other problems as well

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Dono Q ka sense samjha do fixed pt ke abt rotate karne ke do pts h toh confuse ho raha hu please try @mihir @Cooljet123 @complexroots @harsh2 @Aswin24 @Seshank and @others anyone please try this…


For 5 take a point (x,y) and find the slopes of the line connecting the point (x,y) and the given points…( call them tan θ1 and tan θ2 ) … as per the given info, d( θ1)/dt = 2 d( θ2)/dt or θ1=2 θ2

So arctan(m1) = 2 arctan(m2) Sub in the m1 and m2 values and use 2 arctan expansion formula and equate the insider terms of LHS and RHS which gives partial circle eq ig


What abt 1st Q!??

@Karan_Ralhan I am not even able to understand bro, reading again and again…

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Same issue… With me