z=Öx2+y2 = (x2+y2)1/2
fx = partiele afgeleide naar x
fx= x(x2+y2)-1/2 = x
---
(x2+y2)1/2
fy= y(x2+y2)-1/2 = y
---
(x2+y2)1/2
fxx= 1.(x2+y2)1/2 - x.x(x2+y2)-1/2 = quotientregel
-------------------------------------
((x2+y2)1/2)2
= (x2+y2)1/2 - x2(x2+y2)-1/2
-------------------------------------
(x2+y2)3/2
= x+y - x4
----
(x2+y2)1/2
---------------------
(x2+y2)3/2
En dan kom ik helaas vast te zitten.
Studen
Student universiteit - zondag 14 december 2008