Question

Desfaceti parantezele! a) -√2(2x-√2y) b) √7(√2a+√7) (DAU 10 PUNCTE!)

Answer 1

$-\sqrt{2}\left(2x-\sqrt{2}y\right)=-\sqrt{2}\cdot \:2x-\left(-\sqrt{2}\right)\sqrt{2}y=-2\sqrt{2}x+\sqrt{2}\sqrt{2}y=-2\sqrt{2}x+2y$

$\sqrt{7}\left(\sqrt{2}a+\sqrt{7}\right)=\sqrt{7}\sqrt{2}a+\sqrt{7}\sqrt{7}=\sqrt{14}a+7$