single quote



Richard Fateman wrote:
>
> DT -- derivation approximations 

derivation TRANSFORMATIONS, I meant
>  -- e.g. take an expression or two and 
> make another nonequivalent one.  e.g. A+B,  diff(A,x), etc.
>
> Also I/O like plotting.
>
> Now is sin(0) -->  0   an ET or an AT?
>   
RJF