ok so here's my working
so if you draw up x^2 +2x+3 you can see domain is all real x because it never touches 0 and below due to the square root sign so that's domain
onto the range, so just for the quadratic we can see the minimum value/turning point is -1 (just remembered formula is -b/2a whoops). We use the min value bc the smaller the x value the larger the y value for the function.
Using -1 we sub it into the 1/sqrt of x^2 +2x+3 and our maximum value is 0.7071...
as the quadratic HAS to be greater than 0 (bc you can't do 1/0) and also because when doing square root functions you don't get negative (only outputs positive apparently)
range is : 0 < y </ (less than equal to) 0.7071...
(does this make sense or do I need a diagram?)