MathGroup Archive 2006

[Date Index] [Thread Index] [Author Index]

Search the Archive

Mathematica Question


Thanks very much for all those who replied. I really appreciate it.
Unfortunately for the more complicated function that I had, the procedure
did not work. It just returned the expression back to me. Perhaps, this is
because the expression is not negative as I was hoping it to be, or perhaps
because Mathematica could not do it. I don't know which one. Just for
information I am writing down the expression I wanted to check this for.

Suppose U[p,d,rl,rh] = (Log[1+p*d*rh] / Log[1+p*d*rl]) where, 0.2<p<1,
2<d<20, rl > rh > 0. I wanted to find whether the second partial derivative
of this with respect to d is negative. Also, if cross partial with respect
to (d,p) is negative at least for large enough 'p'. For small, p, it can be
seen the ross partial can be positive or negative, which explains why
Mathematica just returns the expression.

Thanks once again to all who replied. These techniques will definitely be
useful to me for other work.

Bharat.



  • Prev by Date: Re: why doesn't the range on this interval match the plot range?
  • Next by Date: Re: Automating PolarPlot with Polar Gridlines
  • Previous by thread: Re: Mathematica Question
  • Next by thread: Re: Mathematica Question