Courses on Khan Academy are always 100% free. Start practicing—and saving your progress—now: https://www.khanacademy.org/math/ap-calculus-ab/ab-integration-new/ab-6-1/v/introduction-to-integral-calculus

The basic idea of Integral calculus is finding the area under a curve. To find it exactly, we can divide the area into infinite rectangles of infinitely small width and sum their areasÑcalculus is great for working with infinite things! This idea is actually quite rich, and it's also tightly related to Differential calculus, as you will see in the upcoming videos.

Watch the next lesson: https://www.khanacademy.org/math/ap-calculus-ab/ab-accumulation-riemann-sums/ab-def-integral/v/definite-integrals-intro?utm_source=YT&utm_medium=Desc&utm_campaign=APCalculusAB

Missed the previous lesson? https://www.khanacademy.org/math/ap-calculus-ab/ab-applications-derivatives/ab-motion-diff/v/rectilinear-motion-example-maximum-acceleration?utm_source=YT&utm_medium=Desc&utm_campaign=APCalculusAB

AP Calculus AB on Khan Academy: Bill Scott uses Khan Academy to teach AP Calculus at Phillips Academy in Andover, Massachusetts, and heÕs part of the teaching team that helped develop Khan AcademyÕs AP lessons. Phillips Academy was one of the first schools to teach AP nearly 60 years ago.

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