Equation of the sphere which touches the plane 3x+2y−z+2=0 at the point (1,−2,1) and cuts orthogonally the sphere x²+y²+z²−4x+6y+4=0
a) (x+7/2) ²+(y+5) ²+(z−5/2) ²=(3√14/2) ²
b) (x−7/2) ²+(y−5) ²+(z+5/2) ²=(3√14) ²
c) (x−7/2) ²+(y+10) ²+(z+5) ²=(3/2) ²
d) (x+7) ²+(y−10) ²+(z−5) ²=(3) ²
