$$3x^2+18x-20$$

$$-\left\{5+\left[3-132:\left(-2\right).7\right]\right\}$$

$$x^2\:+\:4y^2\:+\:5z^2\:=\:6\:$$

$$x\sqrt{1-x^2}dx+y\sqrt{1-y^2}dy=0$$

$$\int x\left(3x+6\right)dx$$

$$2x^5-8x^2+4$$

$$7\cdot4\cdot2\cdot8$$