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With 552 functions, the Citiplus Scientific Series SX-991EX Calculator handles engineering and advanced mathematics. Non-programmable. Battery plus solar. Under the hood, dual power sources maintain uptime. Across the 12-digit natural textbook display, fractions and roots appear as they do in print. Compared to the SX-991MS, this version adds 151 functions and swaps the 2-line screen for high-resolution dot matrix.
Key Features
- 12-Digit High Resolution Display: 192 x 63 dot matrix screen output for clarity. Large digits stay legible under bright overhead lighting.
- 6-Month Service Warranty: Manufacturer support for internal hardware and circuit board defects. Covers circuit failure during regular student use.
- Dual Power Supply: Solar cell and LR44 battery backup for constant power. Prevents shutdown during load shedding.
- 552 Integrated Functions: Equation solver and spreadsheet capabilities for advanced math tasks. Handles complex matrix calculations without external software.
- Natural Textbook Display: Input and output matching mathematical notation in printed books. Reduces tranion errors during complex equation entry.
Frequently Asked Questions
Is Citiplus SX-991EX good for engineering?
This model supports 552 functions including matrix, vector, and statistical analysis. It covers the technical requirements for most university engineering curricula.
How many functions in Citiplus 991EX?
The internal processor contains 552 unique mathematical functions. This represents a 151-function increase over the previous MS-series version.
