Riemann Sums:
Rectangles and Trapezoids are used for the area under graphs (approximation).
Used mostly with:
Linear Functions and Absolute Values Functions

Subintervals:
The amount of areas/trapezoids/rectangles.

Trapezoidal Rule:
Height(h): The x-axis change.
B1 and b2: The y-axis changes.

Left and Right Rectangle Riemann Sums:
Left Riemann Sum skips the last point.
Right Riemann Sum skips the first point.

Midpoint Riemann Sum:
Uses midpoint of the subinterval/rectangle width.
Most accurate and best for A LOT of data.
It’s also the average of left and right triangle Riemann Sums

Graphical Representation of the different Sums: