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Full Version: higher derivatives of implicit equation?
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Can higher order derivatives be obtained in CAS, (without programming)?

Example:
z:=(3*x^2-y^2) = 16,
simplify(implicit_diff(z,x,y))
leads to 3*x /y as the first derivative of z.

How would one obtain the (Second derivative): d^2y/dx^2=(3*y-3*x*3*x/y)/y^2 (or simplified equivalent)?

-Dale-
simplify(implicit_diff(z,x,y,2)) works for me on the latest version. So next update (if any) should have it being very simple at least. Thank you kind sir. (I should have thought to try that!)
-Dale-
I have tried that on my Prime with software 2017 07 10 (12066) and cas 1.1.2-11
and the command implicit_diff(z,x,y,2) gace Error Bad Argument Value
Yes, we mere mortals will have to wait for the next firmware update (if any!) . . . maybe more XCAS commands will be implemented as well, as discussed here

``` idiff(eq,x,y,n):=begin   local j,dn,d1;   d1:=-diff(eq,x)/diff(eq,y);   dn:=d1;   for j from 2 to n do     dn:=diff(dn,x)+diff(dn,y)*d1;   end;   return dn; end```