1)   Desktop calculator - DesktopCalc 2.0
DesktopCalc is an enhanced, easy-to-use and powerful scientific calculator with an expression editor, printing operation, result history list and integrated help.
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 2)   Compact Calculator - CompactCalc 4.2
CompactCalc is an enhanced scientific calculator for Windows with an expression editor. It embodies prime numbers, rational numbers, generic floating-point routines, hyperbolic and transcendental routines.
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 3)   Multivariable Calculator - SimplexCalc 4.1
SimplexCalc is a multivariable desktop calculator for Windows. It is small and simple to use but with much power and versatility underneath. It can be used as an enhanced elementary, scientific, financial or expression calculator.
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