1.
The value of lim⁡n→∞1+2−3+4+5−6+…+(3n−2)+(3n−1)−3n2n4+4n+3−n4+5n+4\lim\limits_{n \to \infty} \frac{1 + 2 - 3 + 4 + 5 - 6 + \ldots + (3n - 2) + (3n - 1) - 3n}{\sqrt{2n^4 + 4n + 3} - \sqrt{n^4 + 5n + 4}} is