Derivatives expressed as limits | Advanced derivatives | AP Calculus BC | Khan Academy

Sal interprets an elaborate limit expression as 5 times the derivative of log(x) at x=2. This way, he can evaluate the limit using differentiation rules instead of directly analyzing the limit (which is hard!).

AP Calculus BC on Khan Academy: Learn AP Calculus BC - everything from AP Calculus AB plus a few extra goodies, such as Taylor series, to prepare you for the AP Test

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