Derive

Hi,

tomorrow I have my mathsexam, but I want to check some equations and extra exercices etc. for that I need Derive, because I'm already familiar with that program. Is there anyone who knows, where I can download the full version or how I can get another trialversion of 30 days? Just reinstalling the trial doesn't work and I've checked in registry and there's nothing that looks like being from derive. :<

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