Thread: Partial derivative of second order from numerical values

1. Partial derivative of second order from numerical values

I am asked to estimate the value of $\displaystyle f_{xy}''(3;4)$ in

$\displaystyle f_x'(3;4) = -5$

$\displaystyle f_y'(3;4) = 2$

How do I find $\displaystyle f_{xy}''(3;4)$ from there?

Thanks a lot!

2. Originally Posted by mathieumg
I am asked to estimate the value of $\displaystyle f_{xy}''(3;4)$ in

$\displaystyle f_x'(3;4) = -5$

$\displaystyle f_y'(3;4) = 2$

How do I find $\displaystyle f_{xy}''(3;4)$ from there?

Thanks a lot!
Estimate $\displaystyle f_y(2;4)$, $\displaystyle f_y(3,4)$ and $\displaystyle f_y(4;4)$ and use these to extimate $\displaystyle f_{yx}(3,4)$ or better yet look up even better methods in Abramowitz and Stegun

CB