Scientific Calculator Precision 81

Scientific Calculator Precision 81 is a scientific calculator for scientists, engineers, teachers, and students. 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