Circle And System Of Circles Question 349

Question: Radius of the circle $ x^{2}+y^{2}+2x\cos \theta $ $ +2y\sin \theta -8=0 $ , is

[MNR 1974]

Options:

A) 1

B) 3

C) $ 2\sqrt{3} $

D) $ \sqrt{10} $

Show Answer

Answer:

Correct Answer: B

Solution:

$ R=\sqrt{{{\cos }^{2}}\theta +{{\sin }^{2}}\theta +8}=3 $