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I have to prove a property $P(x)$ hold for $\forall x: x \in (0,1]$. I also have a property $F\big(\frac{x}2\big)=F(x)+1$ which is key to prove $P(x)$. If I prove following steps:

  1. $P(x-\epsilon)$ holds for $\forall \epsilon$,where $\frac{x}{2}<x-\epsilon<x$

  2. $P\big(\frac{x}{2}\big)$ holds

  3. $\forall x \in (0,1],\space \space \exists \frac{x}{2} \in (0,1]$.

It this a correct way to prove using induction over real number?

Tom
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1 Answers1

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You're not the only one asking this question. Pete Clark has given it a lot of thought and gives a good answer in this discussion.