Finding the slope of a tangent line to a curve (the derivative). Introduction to Calculus. Watch the next lesson: https://www.khanacademy.org/math/differential-calculus/taking-derivatives/derivative_intro/v/calculus-derivatives-2?utm_source=YT&utm_medium=Desc&utm_campaign=DifferentialCalculus Missed the previous lesson? https://www.khanacademy.org/math/differential-calculus/taking-derivatives/derivative_intro/v/formal-and-alternate-form-of-the-derivative-example-1?utm_source=YT&utm_medium=Desc&utm_campaign=DifferentialCalculus Differential calculus on Khan Academy: Limit introduction, squeeze theorem, and epsilon-delta definition of limits. About Khan Academy: Khan Academy is a nonprofit with a mission to provide a free, world-class…