Given inequation is x2+6x+13>0.
Here, factorization is not possible.
Rewriting the given inequation, we get,
(x2+6x+9)+4>0
(x+3)2+4>0
We know that (x+3)2≥0 for every x∈R.
(x+3)2+4≥4>0 for every x∈R.
Therefore, the required solution is the set of all real numbers, i.e., (−∞,∞).