(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Let z = f(x,y) be a differentiable function on R^2 such that f(1, 2) = 3,

f(1.2, 2.3) = 3.4 and f(0.9, 2.1) = 3.2.

a) Estimate dz/dx and dz/dy at (1,2) (dz/dx and dz/dy are partial derivatives)

b) Estimate the value of the directional derivative of z = f(x,y) at the point (1,2) as you move towards (2,3)

2. Relevant equations

3. The attempt at a solution

I've tried using the formal definitions of directional and partial derivatives to do these but I just can't get how the estimates come in. Help would be very much appreciated

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# Homework Help: Estimating partial derivatives/directional derivatives

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