$-15a^2-24a^2$

$\int_{-\infty}^f\left(3u\left(x+2\right)\right)dx$

$\left(01.4\right)\cdot\left(-30.6\right)$

$\frac{a^4}{a^7}$

$-3x^2y+12xy^2$

$8\left(9x+5\right)-9x$

$\frac{sin\left(2x\right)}{2sin\left(x\right)}+tan\left(x\right)sin\left(x\right)=sec\left(x\right)$