Unprepared, unrehearsed, unscripted, and even incorrect, this is a shameful statement on the academy. I am completely new to the calculus, but I know enough of the prerequisites to know that (2^2+4)(2+2) does not equal 8+4, as the "instructor" asserts in lesson 5 as he moves on without correcting his mistake, giving the wrong answer to the example limit, frustrating anyone who attempt to actually work out the problems before watching his solutions. Enough, for me.
Hxhxthgvgddh about Khan Academy: Calculus 1