Question

помогите пж срочно по алгебре 8 класс ​

Answer 1

$(x+\sqrt{y})(x+\sqrt{y})=(x+\sqrt{y})^2=x^2+2x\sqrt{y}+y\\\\\\(\sqrt{x}+\sqrt{xy})^2=x+2\sqrt{x^2y}+xy=x+2x\sqrt{y}+xy=x(1+y+2\sqrt{y})\\\\\\(3\sqrt6-2\sqrt3)^2=9\cdot 6-2\cdot 3\sqrt6\cdot 2\sqrt3+4\cdot 3=54-12\sqrt{18}+12=\\\\=66-36\sqrt2=6\cdot (11-6\sqrt2)\\\\\\(4\sqrt5-7\sqrt5)^2=\Big (\sqrt5\cdot (4-7)\Big )^2=\Big (\sqrt5\cdot (-3)\Big )^2=5\cdot 9=45$