$$\frac{\sec\left(x\right)}{\sec\left(x\right)+1}+\frac{\sec\left(x\right)}{\sec\left(x\right)-1}$$

$$4y-1=15$$

$$a^2+30ab$$

$$\frac{6dy}{dx}+24x=4$$

$$\left(t^2+36\right)\frac{dy}{dx}=\left(x^2+9\right)$$

$$\int\frac{5x^2}{9-x^2}dx$$