How to find the smallest n for inequality involving factorial, $n! > 10^6 $, what is $n$?

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How to find the smallest n for inequality involving factorial, $n! > 10^6 $, what is n?

I solved it using calculator, that is the answer is $n \approx 9$. How to solve this inequality?

Smallest $n$ giving $n! > 10^6$ ?

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$$ \begin{align*} 9!&=1\cdot2\cdot3\cdot4\cdot5\cdot6\cdot7\cdot8\cdot9\\ &=(2\cdot5)(3\cdot7)(4\cdot6)(8\cdot9)\\ &<10\cdot 30\cdot 30\cdot 80\\ &<8\cdot10^5\\ &<10^6. \end{align*} $$ and $$ \begin{align*} 10!&=1\cdot2\cdot3\cdot4\cdot5\cdot6\cdot7\cdot8\cdot9\cdot10\\ &=(2\cdot5)(3\cdot7)(4\cdot6)(8\cdot9)\cdot10\\ &>10\cdot 20\cdot 20\cdot 70\cdot 10\\ &=28\cdot10^5\\ &>2\cdot10^6\\ &>10^6. \end{align*} $$