$$-y^2-y^2$$

$$\left(x+3\right)\left(x-4\right)+\left(x+3\right)\left(x+4\right)$$

$$\int\left(3x+4\right)^{-6}dx$$

$$x^3=81x$$

$$2-\csc^2z$$

$$\int\left(t^2+3t+4\right)\cdot\cos\left(2t\right)dt$$