Riemann Sums for Functions
Type the expression of the function
Adjust the graphics area properly with xmin, ymin, xmax, ymax
Give the lower and upper bounds for integral (You can also move them directly along the x-axis)
Give the number of subintervals or slide it. You can also change the limits of the slider.
Define the position of calculation point on subinterval (0 (left) to 1 (right))