I've posted my version of findroot on the examples repository, as well as all the files from last night. This includes several versions of sqrt.
Also, I've added a new section to PS6, entitled "Finger Exercises". These are various short exercises related specifically to material we covered in lecture. Like drill problems, they will not be graded.
The name "Finger Exercises" was chosen to evoke images of music lessons, where you often have little exercises just to teach your fingers the notes. I may continue this for future lectures; we'll see.