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Question 11.4.2: Find the equation for the sphere with centre at (−2,−2,−2) a......

Find the equation for the sphere with centre at (−2,−2,−2) and radius 4.

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According to formula (11.4.4), the equation is

(x-a)^{2}+(y-b)^{2}+(z-c)^{2}=r^{2}     (11.4.4)

(x-(-2))^{2}+(y-(-2))^{2}+(z-(-2))^{2}=4^{2}

or

(x+2)^{2}+(y+2)^{2}+(z+2)^{2}=16

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