Good job! If you are observant, you may have noticed that R truncated the result of the previous exercise by one digit. The accurate result for
What R actually displayed was:
What happened? By default R displays up to 7 digits (before and after the decimal point) of the result. The accurate result was 8 digits. R truncated it by removing the last digit.
Note that this only applies when R displays a result. When performing the calculations, R works accurately with numbers that have up to 15 decimal places and doesn't perform rounding in intermediate stages.