Since you have the formula, go ahead and use the formula node. Assuming that I've copied everything correctly, it should look like the attached jpeg file. What I haven't done is anything in regard to extracting the analog inputs from a daq result since I don't know how many total channels you're using or the scan order. That's should be simple for you to implement - just some array indexing.
Also, note the exponetiation notation. It's a little different in older versions of LabVIEW so check your LabVIEW help file to see what is correct for the version you're using.