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**Rapid_W** A snippet from a calculus question however i am finding the simplifying of a rationalisation hard.

This $\displaystyle \frac{\frac{1}{\sqrt{x+h}}-\frac{1}{\sqrt{x}}}{h}$ needs to be rationalised

now i know i multiply both top and bottom by $\displaystyle \frac{1}{\sqrt{x+h}}+\frac{1}{\sqrt{x}}$

but I'm having mega difficulty actually doing it and getting an equation that actually looks half decent at the end, if someone could just show me step by step, how to really simplify the equation I would be extremely grateful. Thanks.