Square Root

How can I enter, for example, square root X+3 into the function box? I can create a set of points and plot the graph with these pointrs but I would like to enter the square root directly.

Which version of the program are you using?
For older versions you can use the root() function as follows:
root(x+3)

In the newer versions you can simple press Ctrl+R in order to insert the root sign, then followed by (x+3) as shown here:

Thanks for the prompt reply. It works fine. Why didn't I think of that?

I tried sqrt (x+3) but that didn't work. If only I had tried root (x+3)

It looks like many people try sqrt first since it's the popular form for squared root. In future version I will have it so that it will work for all 3 alternatives