Let's evaluate the limit of $\frac{1}{x^2}$ when $x\to \mathrm{+\infty }$

ⓘ A quantity that grows without bound raised to a positive power still grows without bound, to a negative power it tends to 0

The limit of $x^2$ is $\mathrm{+\infty }$ when $x\to \mathrm{+\infty }$

ⓘ A number divided by a quantity that grows without bound tends to 0

So the limit of $\frac{1}{x^2}$ is $0$⁺ when $x\to \mathrm{+\infty }$

▶Limit:   $0$