Question

How do you graph `y = | x^2 - 1 |`?

Answer 1

See graph.

Explanation:

First consider the graph of `x^2-1`

graph{x^2 -1 [-10, 10, -5, 5]}

Now the absolute value of that same function, just switch all the negative results to positive:

graph{y = | x^2 - 1 | [-10, 10, -5, 5]}