$$\left(x^a+2a^x-3b^yz\right)\left(-3xabz\right)$$

$$\frac{3x^2}{\left(x^3+1\right)^2}$$

$$\left(a^2+3-3b^2\right)\left(\left(a^2+3\right)^2+3b^2\left(a^2+3\right)+9b^4\right)$$

$$\lim_{x\to0}-\left(3-\frac{2}{x}\right)^{x^2}$$

$$13\left(5\right)+13\left(2\right)$$

$$\frac{2}{3}y+\frac{1}{5}y-y$$

$$\lim_{x\to0}\frac{1}{x}-\csc\left(x\right)$$