B= 1 2 3 4 5 6 2 + 8 + 24 + 77 + 176 + 352 15/10/2021 Bởi Katherine B= 1 2 3 4 5 6 2 + 8 + 24 + 77 + 176 + 352
Đáp án: `=21/22` Giải thích các bước giải: `B=1/2+2/8+3/28+4/77+5/176+6/352` `=1/(1.2)+2/(2.4)+3/(4.7)+4/(7.11)+5/(11.16)+6/(16.22)` `=1/1-1/2+1/2-1/4+1/4-1/7+1/7-1/11+1/11-1/16+1/16-1/22` `=1/1-1/22` `=21/22` Bình luận
Đáp án+Giải thích các bước giải: $\dfrac{1}{2}+\dfrac{2}{8}+\dfrac{3}{28}+\dfrac{4}{77}+\dfrac{5}{176}+\dfrac{6}{352}\\=\dfrac{1}{1.2}+\dfrac{2}{2.4}+\dfrac{3}{4.7}+\dfrac{4}{7.11}+\dfrac{5}{11.16}+\dfrac{6}{16.22}\\=1-\dfrac{1}{2}+\dfrac{1}{2}-\dfrac{1}{4}+\dfrac{1}{4}-\dfrac{1}{7}+….+\dfrac{1}{16}-\dfrac{1}{22}\\=1-\dfrac{1}{22}\\=\dfrac{21}{22}$ Bình luận
Đáp án:
`=21/22`
Giải thích các bước giải:
`B=1/2+2/8+3/28+4/77+5/176+6/352`
`=1/(1.2)+2/(2.4)+3/(4.7)+4/(7.11)+5/(11.16)+6/(16.22)`
`=1/1-1/2+1/2-1/4+1/4-1/7+1/7-1/11+1/11-1/16+1/16-1/22`
`=1/1-1/22`
`=21/22`
Đáp án+Giải thích các bước giải:
$\dfrac{1}{2}+\dfrac{2}{8}+\dfrac{3}{28}+\dfrac{4}{77}+\dfrac{5}{176}+\dfrac{6}{352}\\=\dfrac{1}{1.2}+\dfrac{2}{2.4}+\dfrac{3}{4.7}+\dfrac{4}{7.11}+\dfrac{5}{11.16}+\dfrac{6}{16.22}\\=1-\dfrac{1}{2}+\dfrac{1}{2}-\dfrac{1}{4}+\dfrac{1}{4}-\dfrac{1}{7}+….+\dfrac{1}{16}-\dfrac{1}{22}\\=1-\dfrac{1}{22}\\=\dfrac{21}{22}$