Math Is Fun Forum

limpfisch

Member

Registered: 2012-05-08

Posts: 11

Please help me with this problem

On a certain mountain, the elevation z above a point (x, y) in a horizontal xy-plane
at sea level is z = 2500 - x^2/10 - y^2/5   metres.  The positive x-axis points east; the
positive y-axis points north. Suppose that a climber is at the point (15, –10, 2457.5)

if the climber moves southease, what rate will the climber begin to descend at?

i calculated the gradients in the zx direction and in the zy direction, but i'm not sure what the continuation is.

bobbym

bumpkin

From: Bumpkinland

Registered: 2009-04-12

Posts: 109,606

Re: Please help me with this problem

Hi;

This is how I do it.

Subbing in x = 15 and y = -10.

That means you are going downhill, in the direction of steepest descent.

Hope some of that is correct, what did you get?

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