2022TrialShort answer

Q11 (c)

2 marks

Question

Find the vector equation for the sphere $x^2+4x+y^2-6y+z^2=12$ .

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Solution

(x^2+4x+4)+(y^2-6y+9)+z^2=12+4+9

(x+2)^2+(y-3)^2+z^2=25

Centre is $(-2,3,0)$ , radius is $5$ .

\mathbf r-\begin{bmatrix}-2\\3\\0\end{bmatrix}=5

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Syllabus alignment

Vectors

Vectors and vector equations of linesUse coordinates and vector equations for curves, lines, line segments and spheres in two and three dimensions.

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