Question

Can someone please help me with this calculus problem? I am sooo lost.

Approximate the area under the graph of f(x) and above the x-axis using the following methods with n=4.

A. Use right endpoints
D. Use midpoints

Answer 1

f(x) = x^2 from x=1 to x=5

Answer 2

You do need the graph for it.
The idea is to split the area under graph into n rectangles. To calculate the area of these you just need multiplication.
This is an approximation only. However when you increase n it gets more and more precise

Answer 3

right..

Answer 4

Here is a tutorial : http://tutorial.math.lamar.edu/Classes/CalcI/AreaProblem.aspx