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# 3D question? watch

1. Not too sure how to attempt this one...

Find the minimum distance from the origin to the hyperbolic paraboloid

Only thing I can think of is something to do with the gradient...
2. Simplest thing is to minimize the distance squared.
3. (Original post by DFranklin)
Simplest thing is to minimize the distance squared.
Umm...and how would I go about doing this?
4. Write down the expression for R^2 (I would consider z as a function of x and y, and so R^2 = (x^2+y^2+z^2) can be considered as depending only on x and y). Then differentiate (partially) w.r.t. x and y.
5. (Original post by DFranklin)
Write down the expression for R^2 (I would consider z as a function of x and y, and so R^2 = (x^2+y^2+z^2) can be considered as depending only on x and y). Then differentiate (partially) w.r.t. x and y.
I've got the answer as x=0, y=0, z=1/2. Does this look right?

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