1. The problem statement, all variables and given/known data I need to show that [0,1] and [0,2] have the same cardinality by giving a formula for a function that is bijective. Aren't there a number of functions that can fit this description? Can I then use any one? I'm a little confused, my teacher didn't really elaborate much upon this. Is there a specific formula to find the function, not only in this case, but generally? Edit: I have used y=f(x)=2x, I'm guessing this process is pretty systematic when dealing with such intervals?