$\left(-2\mathrm{ab}^3\right)\cdot\left(1{,}5a^2b\right)$

$3x\left[5\mathrm{xy}-\left(6\mathrm{yx}-9y^2\right)\right]-2y\left(-2x^2\right)$

$10{,}5\, a^3b^4c:\left(-3\mathrm{bc}\right)-\left(-2\right)^2\left(2\mathrm{ab}\right)^3$

$\left(1{,}5u+v\right)\left(-2u+5v\right)$

$\left(x-7\right)\left(x+4\right)-x\left(-2x-3\right)$

$\left(-\dfrac12a+3b\right)\left(1{,}25+\dfrac34\right)\cdot3a-2a\left(b-1\dfrac12b\right)$

$\left(0{,}3x-x+\dfrac7{10}x\right)\left(x+4\right)\left(x^2-3x+1\right)-2\left(x^2-1\right)$

$\left(0{,}5x-1\right)\left(-y+\dfrac23x\right)-\dfrac13\left(x-2\right)x$

$2\left(\dfrac12a\cdot3b\right)+3b\left[0{,}25b-\left(-2a\right)\right]$