$$\frac{dv}{dx}=x\left(v-4\right)$$

$$1.999^2-4$$

$$\cot\left(x\right)\left(1-\cos\left(2x\right)\right)$$

$$\left(+5\right)-\left(-3\right)-\left(-7\right)+\left(+2\right)-\left(+10\right)$$

$$5^3\cdot5^x$$

$$\left(4f+m\right)^4$$

$$\int\frac{1}{x^{2}\sqrt{x^{2}+4}}dx$$