Question

Выражение

Answer 1

$(-b+\sqrt{x})(-b-\sqrt{x})=(b-\sqrt{x})(b+\sqrt{x})=b^{2}-(\sqrt{x})^{2}=b^{2}-x$

Answer 2

$(-b+\sqrt{x})(-b-\sqrt{x})=(-b)^2-(\sqrt{x})^2=b^2-x$