A) 5
B) 4
C) 3
D) 2
Correct Answer: B
Solution :
Given, circle is intersection of sphere. \[{{x}^{2}}+{{y}^{2}}+{{z}^{2}}+2x-2y-4z-19=0\] ... (i) and plane\[x-2y+2z+8=0\] ... (ii) Centre of sphere is (-1, 1, 2). \[P=\] length of the perpendicular from (-1, 1, 2) upon Eq. (ii) \[=\frac{-1-2+4+8}{\sqrt{1+4+4}}=\frac{9}{8}=3\] \[R=\]Radius of the sphere\[=\sqrt{1+1+4+19}=5\] Radius of the circle\[=\sqrt{{{R}^{2}}-{{p}^{2}}}=\sqrt{25-9}\] \[=\sqrt{16}=4\]You need to login to perform this action.
You will be redirected in
3 sec