Circle And System Of Circles Question 174
Question: The centre of the circle $ x=-1+2\cos \theta $ , $ y=3+2\sin \theta $ , is
[MP PET 1995]
Options:
A) (1, -3)
B) (-1, 3)
C) (1, 3)
D) None of these
Show Answer
Answer:
Correct Answer: B
Solution:
Given that $ \frac{x+1}{2}=\cos \theta $ .
Also $ \frac{y-3}{2}=\sin \theta $
$ \Rightarrow {{( \frac{x+1}{2} )}^{2}}+{{( \frac{y-3}{2} )}^{2}}=1 $
$ \Rightarrow {{(x+1)}^{2}}+{{(y-3)}^{2}}=4 $ , whose centre is $ (-1,\ 3) $ .
BETA
