Nokia X is the first android device from Nokia running the forked version of android based on AOSP. By rooting your device you can install Google Play and other related services which are otherwise not possible(at least now).
- Note: The guide is officially posted by XDA member Xlordvk. I am only sharing it.
Follow the below steps to root your Nokia X, X+ or XL.
1. Download the app called Framaroot from here.
2. Install it on your device and open it.
3. There you will see an option "Grandalf."
4. Select it and reboot your device.
5. Your device is successfully rooted.
If you like you can install GAPPS by following this guide.
Source: XDA Developers Forum