solns = solve(17*x^3 + 2*x^2 + 54*x + 5 == 0, x) # a list with two elements

Then you can look at either a or b individually and (I hope) it will look fine. Second, if you look at solns, it looks bad, but view(solns, viewer='pdf') should pop open a PDF file with nice looking output, and you shouldn't see any clipping.