‎Limit of $‎\sum_{n=1}^\infty\frac{x}{\sqrt{n}}-\frac{x}{\sqrt {n+N}}+\sum_{k=1}^N\sum_{n=1}^\infty\frac{1}{\sqrt{n+k+x}}-\frac{1}{\sqrt {n+k}}‎ $‎?

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Consider the functional sequence $$‎\delta‎_N(x)=\sum_{n=1}^{\infty}\left(\frac{x}{\sqrt{n}}-\frac{x}{\sqrt {n+N}}\right)+\sum_{k=1}^N\sum_{n=1}^{\infty}\left(\frac{1}{\sqrt{n+k+x}}-\frac{1}{\sqrt {n+k}}‎ \right)$$‎ ‎By ‎some ‎theorems ‎through ‎my ‎research, I found that $‎\delta‎_N(x)‎$ ‎is ‎convergent on $(-2,+\infty)$‎ as ‎‎$‎‎N\to\infty$ ‎, but I need the limit function of this exactly. Anyone can help me to find it or present a closed form of it?