Browse by Stream
QnA
Home
QnA
Go To Your Study Dashboard

Get Answers to all your Questions

header-bg qa
  • Home
  • Engineering
  • Answer please! - Three circles of radiitouch each other externally. If they have x-axis as a common tangent, then: - Co-ordinate geometry - JEE Main

Three circles of radii a, b, c\; (a<b<c) touch each other externally. If they have x-axis as a common tangent, then:

  • Option 1)

    \frac{1}{\sqrt a} + \frac{1}{\sqrt b} =\frac{1}{\sqrt c}

  • Option 2)

    \frac{1}{\sqrt b} =\frac{1}{\sqrt a} + \frac{1}{\sqrt c}

  • Option 3)

     

    a,b,c are in AP

  • Option 4)

     

    \sqrt a, \sqrt b, \sqrt c, are in AP

Answers (1)

best_answer

 

Distance formula -

The distance between the point A\left ( x_{1},y_{1} \right )\: and \: B\left ( x_{2},y_{2} \right )

is \sqrt{\left ( x_{1} -x_{2}\right )^{2}+\left ( y_{1} -y_{2}\right )^{2}}

- wherein

 

\Rightarrow \sqrt{\left ( b+c \right )^{2}-\left ( b-c \right )^{2}}

=\sqrt{\left ( b+a \right )^{2}-\left ( b-a \right )^{2}}+\sqrt{\left ( a+c \right )^{2}-\left ( a-c \right )^{2}}

\Rightarrow \sqrt{bc}=\sqrt{ab}+\sqrt{ac}

\Rightarrow \frac{1}{\sqrt{a}}=\frac{1}{\sqrt{c}}+\frac{1}{\sqrt{b}}


Option 1)

\frac{1}{\sqrt a} + \frac{1}{\sqrt b} =\frac{1}{\sqrt c}

Option 2)

\frac{1}{\sqrt b} =\frac{1}{\sqrt a} + \frac{1}{\sqrt c}

Option 3)

 

a,b,c are in AP

Option 4)

 

\sqrt a, \sqrt b, \sqrt c, are in AP

Posted by

admin

View full answer

JEE Main high-scoring chapters and topics

Study 40% syllabus and score up to 100% marks in JEE

Similar Questions

Trending Articles/News

anam-khan

JAC Chandigarh Counselling 2025: Round 1 seat allotment result out for BTech admissions
anam-khan

JoSAA round 5 seat allotment result 2025 out on josaa.nic.in

Latest Question