Wieso gibt 6+9^3+6589*2-9/6*log(90+1)= 16 ????

$${\mathtt{6}}{\mathtt{\,\small\textbf+\,}}{{\mathtt{9}}}^{{\mathtt{3}}}{\mathtt{\,\small\textbf+\,}}{\mathtt{6\,589}}{\mathtt{\,\times\,}}{\mathtt{2}}{\mathtt{\,-\,}}{\frac{{\mathtt{9}}}{{\mathtt{6}}}}{\mathtt{\,\times\,}}{log}_{10}\left({\mathtt{90}}{\mathtt{\,\small\textbf+\,}}{\mathtt{1}}\right) = {\mathtt{13\,910.061\: \!437\: \!911\: \!518\: \!359\: \!6}}$$

Das ist großer Quatsch, was Du da aufgeschrieben hast.