#### SLD

##### Contributor

Thus at x=1 and -1 the radius of that circle would shrink to 0 and at x=0 the circle would be its largest with r=1/2.

If you traced the center of all such circles from -1 to 1, is there a formula for that line?

ChatGPT kept saying it is 1/2*sqr(1-x^2). Which is just 1/2 of the circle essentially. But that is clearly wrong. Try it for 0.8 and you will see.