I am not sure if this is the right place, but it does appear in my calculus book.

"

Proove by induction that forall n real, positive numbersa_{1}, a_{2}, a_{3, }..., a_{n}that follow the rule a_{1}a_{2}a_{3}...a_{n }= 1, the following expession is true:

$\displaystyle \sum_{i=1}^{n} a_{i} \geq n $

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I have tried working it out but I couldn't proove the induction step.

I would very appreciate any help with this.