[tex] \lim\limits_{x\rightarrow \infty} \Big[ (x+1)^2 - (x-1)^2 \Big]\overset{\infty - \infty}{=}\\ \\\overset{\infty - \infty}{=} \lim\limits_{x\rightarrow \infty} \Big[(x+1)-(x-1)\Big]\Big[(x+1)+(x-1)\Big] = \\ \\ = \lim\limits_{x\rightarrow \infty} (x+1-x+1)(x+1+x-1) = \\ \\ =\lim\limits_{x\rightarrow \infty} 2\cdot 2x= \\ \\ = \lim\limits_{x\rightarrow \infty} 4x = \infty[/tex]
