The Tangent Line Part 3
Before we move to the next topic, I want you to see that the breadcrumb trail exactly matches
f'(x)=2x+2. To that end, I've zoomed way in.
Adjust A along f(x), and convince yourself that the function f'(x)=2*x+2 exactly encodes the slopes of the tangent lines of f(x). Move on after you've had a close look.