Use sums of the form ∑ 𝑓(𝑥𝑖) 𝛿𝑥𝑖𝑖 to estimate the area under the curve 𝑦 = 𝑓(𝑥).

mm-u4-t1-s1-d1

Interactive

Rectangle sums → the definite integral

manipulative

Left, midpoint, or right rectangles estimate area under y = f(x); scrub n, endpoints, and shape params — compare the sum to the definite integral as n grows.

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