$2ab^2+3ab-5a^2b+4ab^2$

$\frac{\left(3x+3\right)}{2x^2-x-1}$

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

$\left(a-b\right)\left(a^3\right)$

$\int\left(\frac{6}{3x^2+9}\right)dx$

$\frac{\infty^4+3\left(\infty\right)^7-\infty-2}{4\left(\infty\right)-\infty^6-5\left(\infty\right)^2-9\left(\infty\right)^7}$

$\int\frac{1+7\ln\left(x\right)^7}{x}dx$