Im doing the following question:(adsbygoogle = window.adsbygoogle || []).push({});

calculate the directional derivative of the function f(x,y,z) = z/(2x + y) at the point (0,1,1) in the direction d = 2i - 2j - k

could someone please check my answer is correct as i calculated -3i -6k

Also how do i find the unit vector in the direction of the greatest rate of change of the function f(x,y,z)

thanks

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# Homework Help: Directional derivative?

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