\"\"

\

The function is \"\", the equations are \"\" and\"\".

\

\"\" , where \"\" is the right endpoint of the partition.

\

\"\" .

\

\"\" is the width of the \"\" interval.

\

\"\"

\

\"\"

\

\"\"

\

\"\".

\

\"\"

\

\"\"

\

\"\"

\

\"\"

\

\"\"

\

Apply summation formulae.

\

\"\"

\

\"\"

\

\"\"

\

\"\"

\

\"\"

\

\"\"

\

As \"\", then \"\".

\

\"\"

\

\"\"

\

\"\".

\

\"\"

\

\"\".