linux alternative?

[augie]

at ssu we use mathematica for all of our math fun. so now im wondering if 
there is an open-source linux alternative? something that does differential 
equations, intergrals, power series, and other calculus stuff. i know 
mathematica makes a linux version of their product, but $139 is $139! 

augie

-- 
"I will permit no man to narrow and degrade my soul by making me hate him."
	--Booker T. Washington

registered linux user #229905