6/3-√13

6/3=2

So the most simple exact answer is just

$${\mathtt{2}}{\mathtt{\,-\,}}{\sqrt{{\mathtt{13}}}}$$

1.6055512754639893 is the anser also heres how 2 do it  6/3 simly put 2 then the squre root of 13 which is 3.6055512754639893 minus 2 is 1.6055512754639893 the hard part is finding the squre root of 13 (number anser) 6/3 = 2 the squre root of 13 3.6055512754639893 - 2 = 1.6055512754639893