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compute and display the corresponding Riemann sums for any function you \
enter, hence estimating the definite integral of that function on a given \
interval. \n\nHere's how to use it:\n1. \"Activate\" these two routines by \
putting your cursor anywhere on them and then pressing Shift-enter as usual \
(do this for each of the two). \tThere will be no output at this time.\n2. \
Now OPEN A NEW NOTEBOOK (for your output) from the File menu. Define the \
function you want to look at and then invoke the routine you want including \
the endpoints of the interval and the number of subdivisions you want. For \
example, to see the lefthand sums for the function ",
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