$\int\frac{2x-1}{\left(x+1\right)\left(x-2\right)}dx$

$\left(1+\tan\left(a\right)\right)\sec^2\left(a\right)=1$

$\lim_{x\to0}3x^{\frac{1}{x}}$

$\sin\left(x\right)\cdot\tan\left(x\right)-\sin\left(x\right)$

$\log_x\left(14x-45\right)=2$

$\left(5a^3b+6ab^2-4a^2\right)\cdot\left(\frac{-2}{5}ab\right)$

$\frac{2}{\frac{1}{5}}$