A Riemann sum computes an approximation of the area between a curve and the {{MATH_134}}-axis on the interval {{MATH_135}}. It can be defined in several different ways. In our class, it will be defined via left-endpoints, right-endpoints, or midpoints. Here we see the explicit connection between a Riemann sum defined by left-endpoints and the area between a curve and the {{MATH_136}}-axis on the interval {{MATH_137}}: {{CMD_138}} {{ENV_139}} {{CMD_140}} and here is the associated Riemann sum {{MATH_141}}