Khi x=căn 3/4 thì \(M=\dfrac{1+\dfrac{\sqrt{3}}{2}}{1+\sqrt{1+\dfrac{\sqrt{3}}{2}}}+\dfrac{1-\dfrac{\sqrt{3}}{2}}{1-\sqrt{1-\dfrac{\sqrt{3}}{2}}}\)
\(=\dfrac{\sqrt{2}+\sqrt{6}}{\sqrt{2}+\sqrt{2+\sqrt{3}}}+\dfrac{\sqrt{2}-\sqrt{6}}{\sqrt{2}-\sqrt{2-\sqrt{3}}}\)
\(=\dfrac{2\sqrt{3}+2}{2+\sqrt{3}+1}+\dfrac{2-2\sqrt{3}}{2-\sqrt{3}+1}\)
\(=\dfrac{2\left(\sqrt{3}+1\right)}{\sqrt{3}\left(\sqrt{3}+1\right)}+\dfrac{2\left(1-\sqrt{3}\right)}{\sqrt{3}\left(\sqrt{3}-1\right)}=0\)
Đúng 0
Bình luận (0)
