HP 40 series

HP 39/40 series are graphing calculators from Hewlett-Packard, the successors of HP 38G. The series consists of six calculators, which all have algebraic entry modes, and can perform numeric analysis together with varying degrees of symbolic calculation. All calculators in this series are aimed at high school level students and are characterized by their ability to download (via cable or infra-red) APLETs or E-lessons. These are programs of varying complexity which are generally intended to be used in the classroom to enhance the learning of mathematics by the graphical and/or numerical exploration of concepts.

The HP 39G (F1906A) was released in 2000.

Basic characteristics:

HP 40G (F1907A) was released in 2000 in parallel with the HP 39G. The HP 40G's operating system is identical to the HP 39G. Differences detected in hardware during start-up trigger the differences in software functionality.

The hardware is identical to the HP 49G/39G series (complete with rubber keyboard). In contrast to the 39G, it integrates the same computer algebra system (CAS) also found in the HP 49G, HP CAS. Unlike its "bigger brothers", the HP 40G has no flags to set/mis-set resulting in a "better behaved" calculator for straightforward math analysis. Additionally the HP 40G does not have infrared connectivity, and is limited to 27 variables. A list-based solver, and other handicaps make this simple-to-use calculator less adapted to higher end use. The HP 40G is not allowed for use in many standardized tests including the ACT and SAT tests.

Basic characteristics:

The hp 39g+ (F2224A) was released in September, 2003.

Basic characteristics:

Note: Although an ARM processor is used in this model, the operating system is substantially the same as that of the 39G, with the Saturn chip being emulated on the ARM at a higher speed than was possible for the 39G. The CAS component of the HP 40G's operating system appears to have been totally removed, rather than simply being hidden at start-up.

The HP 39gs (F2223A) was released in June 2006.

Basic characteristics:

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