Hi ppl, ne1 know how to approach this one?(adsbygoogle = window.adsbygoogle || []).push({});

Given P(1,4,-1), Q(1,2,-1) and R (3,2,-2), show that PQR is right angled and hence find the equation of the smallest sphere S which passes through P,Q and R.

Okay, I got the right angle by showing PQ and QR to be perpendicular with the dot product as zero.

With the equation of the sphere, I'm not sure how to start this, could someone just point me in the correct direction,

Thanks,

Joe

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# Homework Help: Vectory Geometry, problem involving spheres

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