$$16-3\cdot\left|5+\left(-2\right)\cdot\left(-4\right)-21\right|$$

$$\frac{\sin\left(x\right)}{1+\cos\left(x\right)}+\frac{1}{\sin\left(x\right)}+\frac{\cos\left(x\right)}{\sin\left(x\right)}$$

$$x^2-4x+4\le0$$

$$\int\frac{\ln^2\left(x\right)}{x^{\frac{5}{3}}}dx$$

$$-\left(+2\right)-\left(+1\right)-\left(-4\right)$$

$$\int ln\:\left(x+10\right)dx$$

$$\sqrt{10^2-9^2}$$