Amazon.com has a Texas Instruments TI-89 Advanced Graphing Calculator for $99.99 with Free Shipping.
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- Over 500 KB memory for storing functions, programs, and data n
- Pretty Print technology displays mathematical expressions as they appear in textbooks n
- High-resolution display with split-screen views n
- Computes symbolic solutions to differential equations n
- Input/output port and cable; also supports optional TI-GRAPH LINK