If you watched our last episode -- and really, if you haven't, you should.
You now know all about derivatives, and how to use them, to describe the way an equation is changing.
Which means that now we can talk about the other main part of calculus -- basically, the inverse of derivatives, called integrals.
Integrals are useful because they also tell you a lot about an equation: If you plotted an equation on a graph, the integral is equal to the area between the curve and the horizontal axis.
Finding an integral is a little less straightforward than finding a derivative, but, as with derivatives, there are shortcuts we can use to make things a little easier.
We'll even be able to use integrals to talk about how things move -- specifically, the equation we've been calling the displacement curve, and why it looks the way it does.
So let's get started. Say you want to know how high your bedroom window is above the ground outside below.
But you don't have anything to measure it with -- just a ball, the stopwatch app on your phone, and your impressive knowledge of physics.
The force of gravity is what makes the ball fall, so you know that its acceleration is small g 9.81 ms^2, downward.
But you're trying to find its change in position -- how far it falls.
