How do i write 5 square root?

There is a square root sign on the calc

 

Or    sqrt (5)  or

 

If you use the maths formula button you ca enter  sqrt (5) and it will disply properly.

 

Or

 

5^(1/2)   or     5^0.5

 

^ means power of

 

There are other ways as well.

 

This is probably enough.   LOL