>Here's one: plot 360 degrees of a sine wave, and it's first and second derivatives. Then explain an Excel user how that works.
Seems pretty straightforward to me
x <- seq(from = 0, to = 2*pi, by = .05)
y <- sin(x)
y2 <- cos(x)
y3 <- -sin(x)
plot(x, y, type = 'l')
lines(x, y2, col = 'red')
lines(x, y3, col = 'blue')
Sure, I didn't think about my example well enough - what I meant was a generic way of taking a derivative, from series of data to a function that returns a y value for a given x value. E.g. plot derivatives of a normal distribution curve.
Seems pretty straightforward to me