$\"\"$

The function $\"\"$ is decreasing function.

The integral is $\"\"$ .

In this case $\"\"$ .

The number of subintervals are $\"\"$ .

Width $\"\"$

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$\"\"$ .

The function is decreasing, the right end points result in a lower sum and the left end points result in a upper sum.

Lower sum is $\"\"$ . The right end points are $\"\"$ .

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Lower sum is $\"\"$ .

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Upper sum is $\"\"$ .

The right end points are $\"\"$ .

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Upper sum is $\"\"$ .

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Lower sum is $\"\"$ .

Upper sum is $\"\"$ .