Browse by Stream
QnA
Home
QnA
Go To Your Study Dashboard

Get Answers to all your Questions

header-bg qa
  • Home
  • Engineering
  • What is the equation of tangent from Point P(2,1) to the circle  <div c

What is the equation of tangent from Point P(2,1) to the circle x^2+y^2=1 

Option: 1

4x-3y-5=0\\


Option: 2

3x+4y+5=0\\


Option: 3

3x-4y+5=0\\


Option: 4

None of these


Answers (1)

best_answer

 

\\ \text{Given circle is }x^2+y^2=1\\ \text{Let the tangent be}: \mathrm{y}=\mathrm{mx}+\mathrm{1} \sqrt{\left(1+\mathrm{m}^{2}\right)}\\ (2,1) \text{ lies on the tangent so }\\ 1=2m+\sqrt{(1+m^2)}\\ 1-2m=\sqrt{(1+m^2)}\\1+4m^2-4m=1+m^2\\

\\3m^2-4m=0\\m=0, \frac{4}{3}

\\\text{Equation of tangents }

(y - 1) = 0.(x - 2) and  (y - 1) = 4/3.(x - 2)

y = 1 and 4x - 3y - 5 = 0

Posted by

shivangi.shekhar

View full answer

JEE Main high-scoring chapters and topics

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

Similar Questions