Scientific Calculator Precision 81 is a scientific calculator for scientists, engineers, teachers, and students. It follows classical approach when uncertainty of f(x) calculation is estimated by formula max|(derivative(f))|*|x*uncertainty(x)|, where maximum of function derivative is considered on interval [x-uncertainty(x), x+uncertainty(x)]. Thus sin(2*pi)=0+-1E-81 and sin(2*1E20*pi)=0+-1E-61. As we see, the result’s accuracy degrades with growth of argument, but such approach allows to preserve all trigonometry facts like sin(even number*pi+x)=sin(x).

In the default mixed mode the calculator treats numbers as integers wherever it is possible. Σ and Π has three levels of nesting. There are 10 variables (or constants) available for storing frequently used numbers. All calculation results are reflected in History rich-text-box, which can be saved in file or printed.
Unlimited number of user constants can be entered and maintained by user. Fundamental constants are available in the prebuilt Common Constants list.

This calculator follows classical approach when uncertainty of f(x) calculation is estimated by formula max|(derivative(f))|*|x*uncertainty(x)|, where maximum of function derivative is considered on interval [x-uncertainty(x), x+uncertainty(x)]. Thus sin(2*pi)=0+-1E-81 and sin(2*1E20*pi)=0+-1E-61. As we see, the result's accuracy degrades with growth of argument, but such approach allows to preserve all trigonometry facts like sin(even number*pi+x)=sin(x).

Scientific Calculator Precision 81 has internal precision 90 digits that allows to perform division (the most difficult operation) with precision 81 digits, standard functions (power, logarithm, trigonometric functions, hyperbolic functions) with precision 79-81 digits, and Gamma Function, Lower Incomplete Gamma Function, Upper Incomplete Gamma Function with precision 69-81 digits .

The license of this software is Free Trial Software, the price is $35.00, you can free download and get a free trial.