Find all the asymptote of $1-x+\sqrt{2+2x+x^2}$ I find 
$$\lim_{x\rightarrow\infty}1-x+\sqrt{2+2x+x^2}=2,$$ but i'am stuck when $x\rightarrow-\infty$ how to find that $y=-2x$ is an oblique asymptote. Any idea? 

define :$$g(x)=\left(1-x+\sqrt{2+2x+x^2}\right)-(-2x)=\lim_{x\to -\infty}1+x +\sqrt{2+2x+x^2}$$
Multiply and devide by the conjugate to get $$g(x)=\frac{1}{1+x-\sqrt{2+2x+x^2}}$$
It is easy now to see that $\displaystyle\lim_{x\to -\infty} g(x)=0$, which means that $y=-2x$ is an asymptote at $-\infty$.
