requesting a caculator

Mathematical calculator is used for evaluation math expressions with arithmetic operations (+-/*^) and functions: sqrt - square root, exp - exponential function, lb - binary logarithm, lg - decimal logarithm, ln - natural logarithm, sin - sine, cos - cosine, tan - tangent, cot - cotangent, sec - secant, csc - cosecant, arcsin - arcsine, arccos - arccosine, arctan - arctangent, arccot - arccotangent, arcsec - arcsecant, arccosec - arccosecant and others