Circle And System Of Circles Question 37
Question: If $ a>2b>0 $ then the positive value of m for which $ y=mx-b\sqrt{1+m^{2}} $ is a common tangent to $ x^{2}+y^{2}=b^{2} $ and $ {{(x-a)}^{2}}+y^{2}=b^{2} $ , is
[IIT Screening 2002]
Options:
A) (7, 3)
B) (7, 4)
C) (7, 8)
D) (7, 2)
Show Answer
Answer:
Correct Answer: A
Solution:
Putting $ x=7 $ , we get $ y^{2}-6y+9=0 $
$ \Rightarrow y=3,\ 3 $
Hence the point of contact is (7, 3).
BETA
