Zoom out

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Two young mathematicians discuss what curves look like when one “zooms out.”

Check out this dialogue between two calculus students (based on a true story):

Devyn: Riley, think about this function: $f(x) = \frac {x^2-2}{x^{2}+2}.$
Riley: Hmmm. If you plot it, the graph looks like this:
Devyn: Right! What I’ve noticed is that if $x$ gets big, then our function looks like a horizontal line.
Riley: I wonder how we find the line?

1 : Guess the $y$ -intercept of this line. Come back and check your answer after reading the Dig-In!

Answers may vary.