$x^6y^8-\frac{6}{5}x^3y^4z^2+\frac{9}{25}z^4$

$-3\left(-1\right)\left(4\left(2\right)\right)$

$\left(-15\right)\left(-3\right)$

$\left(2m+3n\right)\left(12m-3n\right)$

$-\left(-15\right)\:\left(-9\right)$

$\frac{\sin x\cos x}{\tan x}=1-\sin^2x$

$7,5+2,73-19+3,8-59,6-10$