$-4\cdot4.3$

$-3\left(5x+6y-8\right)$

$2x^2-2x-1$

$\frac{\sin\left(x\right)}{\cos^2\left(x\right)\cos\left(x\right)}$

$\frac{tan\left(x\right)+cot\left(y\right)}{\frac{tan\left(x\right)}{tan\left(y\right)}}=tan\left(y\right)+cot\left(x\right)$

$\lim_{x\to3}\frac{x+2}{x-3}$

$\frac{d}{dx}-4\sqrt{6x^6+5e^x}$