A=3737:43-4343×27:2+4+6+....+100 Giúp mình vs các bạn

2 câu trả lời

$\begin{array}{l} A = \dfrac{{3737:43 - 4343:47}}{{2 + 4 + 6 + ... + 100}} = \dfrac{{101.37:43 - 101.43:37}}{{2 + 4 + 6 + ... + 100}}\\\text{Tính:}\,\,B = \,2 + 4 + 6 + .... + 100\\ \text{So các số hạng:}\,\,\,\,\dfrac{{100 - 2}}{2} + 1 = 50\,\,\text{số}.\\ \Rightarrow B = \left( {100 + 2} \right).50:2 = 2550.\\ \Rightarrow A = \dfrac{{101.37:43 - 101.43:37}}{{2550}}\\ = \dfrac{{101\left( {37:43 - 43:37} \right)}}{{2550}} = \dfrac{{101}}{{2550}}\left( {\dfrac{{37}}{{43}} - \dfrac{{43}}{{37}}} \right)\\ = \dfrac{{101}}{{2550}}\left( {\dfrac{{{{37}^2} - {{43}^2}}}{{43.37}}} \right) = \dfrac{{101}}{{2550}}.\dfrac{{ - 480}}{{1591}} = - \dfrac{{101.16}}{{85.1591}}. \end{array}$

 

\[\begin{array}{l} A = \frac{{3737:43 - 4343:47}}{{2 + 4 + 6 + ... + 100}} = \frac{{101.37:43 - 101.43:37}}{{2 + 4 + 6 + ... + 100}}\\ Tinh:\,\,B = \,2 + 4 + 6 + .... + 100\\ So\,\,cac\,\,so\,\,hang:\,\,\,\,\frac{{100 - 2}}{2} + 1 = 50\,\,so.\\ \Rightarrow B = \left( {100 + 2} \right).50:2 = 2550.\\ \Rightarrow A = \frac{{101.37:43 - 101.43:37}}{{2550}}\\ = \frac{{101\left( {37:43 - 43:37} \right)}}{{2550}} = \frac{{101}}{{2550}}\left( {\frac{{37}}{{43}} - \frac{{43}}{{37}}} \right)\\ = \frac{{101}}{{2550}}\left( {\frac{{{{37}^2} - {{43}^2}}}{{43.37}}} \right) = \frac{{101}}{{2550}}.\frac{{ - 480}}{{1591}} = - \frac{{101.16}}{{85.1591}}. \end{array}\]