Suppose $a$ and $b$ are positive real numbers with $a > b$ and $ab = 8.$  Find the minimum value of $\frac{a^2 + b^2}{a - b}.$
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You are a helpful assistant.<|im_end|>
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Suppose $a$ and $b$ are positive real numbers with $a > b$ and $ab = 8.$  Find the minimum value of $\frac{a^2 + b^2}{a - b}.$
Please reason step by step, and put your final answer within \boxed{{}}.<|im_end|>
<|im_start|>assistant

user
8
Suppose $a$ and $b$ are positive real numbers with $a > b$ and $ab = 8.$  Find the minimum value of $\frac{a^2 + b^2}{a - b}.$
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