KCET2008MathematicsCircle
If the circles x²+y²=9 and x²+y²+2 x+2 y+1=0 touch each other internally, then is equal to
Options
- A4 3
- B1
- C4 3
- D- 4 3
Correct answer
A. 4 3
Step-by-step solution
Centres and radii of the given circles x²+y²=9 and x ²+ y ²+2 x +2 y +1=0 is C ₁(0,0), r ₁=3 and C₂(- , 1) and r₂= ²+1-1 =| | Since, two circles touch internally, array lrl & C ₁ C ₂ & = r ₁- r ₂ & ²+1² & =3-| | array ²+1=9+ ²-6| | 6| |=8 | |= 4 3 = 4 3