eq:''diff(x + y =a, x);solve([eq],[dy/dx]);



[Jorge Barros de Abreu , Sat, 23 Apr 2005 13:57:02 -0300]:
> Hi for all.
> How I make the following situation?
> 
> depends(y,x);
> eq:''diff(x + y =a, x);

This differentiates both sides of the equation with respect to x.  The
result is the equation 1 = 0.

> solve([eq01],[dy/dx]);

I suspect you want something like

diff(ev(y, solve(x+y=a, y)), x); ==> -1 //

HTH,

Albert.