Question 11.4.3: How do you interpret the expression (x + 4)² + (y − 3)² + (z......

Essential Mathematics for Economic Analysis [1185377]

How do you interpret the expression (x + 4)² + (y − 3)² + (z + 5)²? As: (i) the sphere with centre at the point (−4, 3,−5), (ii) the distance between the points (x, y, z) and (−4, 3,−5), or (iii) the square of the distance between the points (x, y, z) and (−4, 3,−5)?

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Only (iii) is correct.

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