I need help checking an expression

Questions
1

I have edited this great activity for a course I am teaching. On slides 6 and 7 the students input an expression to correct an error the machine makes. I have a working check on slide 6, but it won’t work on slide 7. Can someone help me with slide 7? Thanks so much.

011-38 Formulas

2

Maybe try rounding the key functions?

3

I would use pattern matching, here. Something like this:

p= patterns
expr= p.radical(p.fraction(p.literal("V"),
                          p.product(p.literal("\pi"),p.literal("h")) ) )

correct = 
expr.matches(this.latex)
4

Thanks so much, this works.