Các câu hỏi tương tự
CMR\(\frac{1}{\sqrt{2}+\sqrt{3}}+\frac{1}{\sqrt{3}+\sqrt{4}}+...+\frac{1}{\sqrt{79}+\sqrt{80}}>4\)
CMR:
\(\frac{1}{\sqrt{1}+\sqrt{2}}+\frac{1}{\sqrt{3}+\sqrt{4}}+\frac{1}{\sqrt{5}+\sqrt{6}}+....+\frac{1}{\sqrt{79}+\sqrt{80}}>4\)
\(Chứngminh:\frac{1}{1+\sqrt{2}}+\frac{1}{\sqrt{3}+\sqrt{4}}+...+\frac{1}{\sqrt{79}+\sqrt{80}}>4\)
chưngs minh S=\(\frac{1}{1+\sqrt{2}}+\frac{1}{\sqrt{3}+\sqrt{4}}+....+\frac{1}{\sqrt{79}+\sqrt{80}}>4\)
Cho A=\(\frac{1}{\sqrt{1}+\sqrt{2}}+\frac{1}{\sqrt{3}+\sqrt{4}}+.................+\frac{1}{\sqrt{79}+\sqrt{80}}\)
CM A>4
cho A = \(^{\frac{1}{\sqrt{1+\sqrt{2}}}+\frac{1}{\sqrt{3+\sqrt{4}}}+...+\frac{1}{\sqrt{79+\sqrt{80}}}}\)
chứng minh A>4
CMR: \(\frac{1}{\sqrt{1}+\sqrt{2}}\) + \(\frac{1}{\sqrt{3}+\sqrt{4}}\)+ \(\frac{1}{\sqrt{5}+\sqrt{6}}\)+ ....+\(\frac{1}{\sqrt{79}+\sqrt{80}}\)>4
Chứng minh:
B=\(\frac{1}{\sqrt{1}+\sqrt{2}}\) + \(\frac{1}{\sqrt{3}+\sqrt{4}}\) +\(\frac{1}{\sqrt{5}+\sqrt{6}}\) +.............+\(\frac{1}{\sqrt{77}+\sqrt{78}}\) +\(\frac{1}{\sqrt{79}+\sqrt{80}}\) >4
Giúp mk nha.....!!!!!!
chứng minh B=\(\frac{1}{1+\sqrt{2}}+\frac{1}{\sqrt{3}+\sqrt{4}}+\frac{1}{\sqrt{5}+\sqrt{6}}+...+\frac{1}{\sqrt{78}+\sqrt{79}}>4\)