Answer
$$ -\infty$$
Work Step by Step
Given
$$\lim _{x \rightarrow \infty}\left(x^2-x^4\right)$$
Then
\begin{aligned}
\lim _{x \rightarrow \infty}\left(x^2-x^4\right)&=\lim _{x \rightarrow \infty}x^2\left(1-x^2\right) \\
&=\lim _{x \rightarrow \infty}x^2\lim _{x \rightarrow \infty}\left(1-x^2\right)\\
&= \infty(1- \infty)\\
&= -\infty
\end{aligned}