$$\lim_{x\to\infty}\left(\frac{1}{x}-1\right)\cdot\frac{1}{x^2-2}$$

$$-9\left(1-10m\right)$$

$$-36\cdot4$$

$$\arcsin\frac{x-1}{x+1}=-\frac{\pi}{2}+2\arctan\sqrt{x}$$

$$xy\left(x^2y^3+x^3y^3\right)$$

$$9x+6y$$