Question

[Phạm Thị Minh Tâm]

Rút gọn biểu thức

\(\frac{^{x^2-5}}{x+\sqrt{5}}\)(x khác \(-\sqrt{5}\))

\(\frac{x^2+2\sqrt{2}+2}{x^2-2}\)(x khác \(+-\sqrt{2}\))

Answer 1

[Thiên An]

a)  \(\frac{x^2-5}{x+\sqrt{5}}=\frac{\left(x+\sqrt{5}\right)\left(x-\sqrt{5}\right)}{x+\sqrt{5}}=x-\sqrt{5}\)

b)  \(\frac{x^2+2\sqrt{2}+2}{x^2-2}=\frac{\left(x+\sqrt{2}\right)^2}{\left(x+\sqrt{2}\right)\left(x-\sqrt{2}\right)}=\frac{x+\sqrt{2}}{x-\sqrt{2}}\)