Mosfet as Diode Connected Transistor

Before starting , check the video(link given below) for Drain current vs Gate to source potential graph for nmos in Saturation:
https://www.youtube.com/watch?v=LLYpepZCEC4&t=559s

When the drain and gate of a MOSFET are connected together , a two- terminal device known as a "Diode-connected transistor" results.
Check the video given below for detail explanation:

You can check the video from youtube via this link:

https://www.youtube.com/watch?v=71qOESybdOk&t=852s

Now , let us try to solve some numericals based on this concept:

Example 2:

Example 3: