Manipal MET2010MathematicsThree Dimensional Geometry
Radius of the circle gathered r ^2+ r (2 i -2 j -4 k )-19=0 r ( i -2 j +2 k )+8=0, is gathered
Options
- A5
- B4
- C3
- D2
Correct answer
B. 4
Step-by-step solution
Given, eircle is intersection of sphere. x^2+y^2+z^2+2 x-2 y-4 z-19=0...(i) and plane x-2 y+2 z+8=0...(ii) Centre of sphere is (-1,1,2)P= length of the perpendiciar from (-1,1,2) upon Eq. (ii) = -1-2+4+8 1+4+4 = 9 3 =3 aligned & R= Radius of the sphere = 1+1+4+19 =5 & aligned Radius of the circle & = R^2-P^2 = 25-9 & = 16 =4 aligned aligned