$$\frac{4\sqrt{x^3}}{3}-\frac{\sqrt{x}}{3}$$

$$7x^2+4x+7$$

$$\frac{25-\left(a\:+\:1\right)^2}{5+\left(a+1\right)}$$

$$\:\frac{-104}{8}$$

$$17-\left(-4\right)\cdot\left(-3+6\right)-2\left|4-5\left(2-3\right)^7\right|^2$$

$$\cos\left(50\right)\cos\left(30\right)+\sin\left(50\right)\sin\left(30\right)$$