Does Δ(Δx)/Δ(Δy) exist in mathematics and physics?
Sorry. I should say:
I mean that Δ(Δx)/Δ(Δy) does not have any physics or mathematical meaning. Do you agree? If not, can you tell me what is the meaning of Δ(Δx)/Δ(Δy)? Sure, you can do any calculation as you want.