Question

Thực hiện phép tính:
\(\frac{\sqrt{15}-\sqrt{5}}{\sqrt{3}-1}+\sqrt{\left(2-\sqrt{5}\right)^2}-2\sqrt{5}\)

Answer 1

Có \(\frac{\sqrt{15}-\sqrt{5}}{\sqrt{3}-1}+\sqrt{\left(2-\sqrt{5}\right)^2}-2\sqrt{5}\)

=\(\frac{\sqrt{5}\left(\sqrt{3}-1\right)}{\sqrt{3}-1}+\left|2-\sqrt{5}\right|-2\sqrt{5}\)

=\(\sqrt{5}-2+\sqrt{5}-2\sqrt{5}=-2\)

Answer 2

\(\frac{\sqrt{15}-\sqrt{5}}{\sqrt{3}-1}+\sqrt{\left(2-\sqrt{5}\right)^2}-2\sqrt{5}\)

\(=\frac{\sqrt{5}\left(\sqrt{3}-1\right)}{\sqrt{3}-1}+2-\sqrt{5}-2\sqrt{5}\)

\(=\sqrt{5}+2-3\sqrt{5}\)

\(=2-2\sqrt{5}=-2,47\)

Nhớ tik mik nha

Answer 3

\(\frac{\sqrt{15}-\sqrt{5}}{\sqrt{3}-1}+\sqrt{\left(2-\sqrt{5}\right)^2}-2\sqrt{5}\)

\(=\frac{\sqrt{5}\left(\sqrt{3}-1\right)}{\sqrt{3}-1}+\sqrt{5}-2-2\sqrt{5}\)

\(=\sqrt{5}+\sqrt{5}-2-2\sqrt{5}\)

\(=-2\)