Răspuns :
Iti dau exemplu la a, dupa te poti descurca si singur/a.
[tex]-2 \sqrt{2} * 3 \sqrt{5} = -\sqrt{2^2 * 2} * \sqrt{3^2 * 5} = -\sqrt{4*2} * \sqrt{9*5} = -\sqrt{8} * \sqrt{45} = -\sqrt{8*45} = -\sqrt{360} = -\sqrt{36*10} = -\sqrt{6^2 * 10} = -6 \sqrt{10} [/tex]
[tex]-2 \sqrt{2} * 3 \sqrt{5} = -\sqrt{2^2 * 2} * \sqrt{3^2 * 5} = -\sqrt{4*2} * \sqrt{9*5} = -\sqrt{8} * \sqrt{45} = -\sqrt{8*45} = -\sqrt{360} = -\sqrt{36*10} = -\sqrt{6^2 * 10} = -6 \sqrt{10} [/tex]