Originally Posted by

**omnivore** PS: It would be great if somebody using a TI89 could solve the above expression and see how long it takes...

Mine took 28 seconds. The input was Code:

nInt(cos($\displaystyle \sqrt{}$(x)+x),x,0,60)

If you use the regular integration function, $\displaystyle \mbox{$\int$}$(), it will take longer since the calculator will first try to integrate the expression symbolically.

And this answers the question in your title: the TI-89 can do symbolic manipulation; the 84+ cannot. Personally, being able to do symbolic integration is much more important to me than having slightly faster numeric integration.