$\lim_{x\to\infty}\left(ln\left(x^2+1\right)-2ln\left(3x+6\right)\right)$

$\int-15x^5\sqrt{x^2+2}dx$

$-4x^3+10x^2-6$

$1,6\cdot12$

$\left(1-cosx\right)^2+2\cdot cotx\cdot senx=1+cos^2x$

$\:8\:x\:-\:12\:y\:+\:32$

$\left(-2u^2-6u-6\right)-\left(-5u^2+6u+3\right)+\left(7u^2+8u+5\right)$