\(x_1^2+x_2^2+x_3^2+2x_1-4x_2-10x_3 -139 = 0\)
\(x_1^2+2x_1+x_2^2-4x_2+x_3^2-10x_3 -139 = 0\)
\(x_1^2+2x_1+1+x_2^2-4x_2+4+x_3^2-10x_3+25 -139 = 0+1+4+25\)
\((x_1+1)^2 +(x_2-2)^2+(x_3-5)^2 -139 = 30\)
\((x_1+1)^2 +(x_2-2)^2+(x_3-5)^2 = 169\)
Kugel um (-1;2;5) mit r=13