papkovkirill [tex] \sqrt{18b} - 3 \sqrt{3a} + \sqrt{12a} - 4 \sqrt{2b} = 3 \sqrt{2b} - 3 \sqrt{3a} + 2 \sqrt{3a} - 4 \sqrt{2b} = - \sqrt{2b} - \sqrt{3a} = -4-3=-7