Tìm x:
\(\frac{x}{2}\)+ \(\frac{x}{6}\)+ \(\frac{x}{12}\)+ \(\frac{x}{20}\)+ . . . + \(\frac{x}{132}\)= 5\(\frac{1}{2}\)
Tìm cả bài giải nữa nhé !
Tìm x;
(\(\frac{1}{2}+\frac{1}{4}+\frac{1}{8}+\frac{1}{16}\)) : x = (\(\frac{1}{2}+\frac{1}{6}+\frac{1}{12}+\frac{1}{20}+.......+\frac{1}{132}\))
\(\left(\frac{1}{2}+\frac{1}{4}+\frac{1}{8}+\frac{1}{16}\right)\div x=\left(\frac{1}{2}+\frac{1}{6}+\frac{1}{12}+\frac{1}{20}+...+\frac{1}{32}\right)\)
\(\left(\frac{8}{16}+\frac{4}{16}+\frac{2}{16}+\frac{1}{16}\right)\div x=\left(\frac{1}{1.2}+\frac{1}{2.3}+\frac{1}{3.4}+\frac{1}{4.5}+...+\frac{1}{11.12}\right)\)
\(\frac{15}{16}\div x=\left(\frac{1}{1}-\frac{1}{2}+\frac{1}{2}-\frac{1}{3}+\frac{1}{3}-\frac{1}{4}+\frac{1}{4}-\frac{1}{5}+...+\frac{1}{11}-\frac{1}{12}\right)\)
\(\frac{15}{16}\div x=\left(\frac{1}{1}-\frac{1}{12}\right)\)
\(\frac{15}{16}\div x=\frac{11}{12}\)
\(x=\frac{15}{16}\div\frac{11}{12}\)
\(x=\frac{15}{16}\times\frac{12}{11}\)
\(\Rightarrow x=\frac{180}{176}=\frac{45}{44}\)
tìm x biết: \(\frac{\left(\frac{1}{2}+\frac{1}{4}+\frac{1}{8}+\frac{1}{16}\right)}{x}=\frac{1}{2}+\frac{1}{6}+\frac{1}{12}+\frac{1}{20}+...+\frac{1}{132}\)
Ta có \(\left(\frac{1}{2}+\frac{1}{4}+\frac{1}{8}+\frac{1}{16}\right):x=\frac{1}{2}+\frac{1}{6}+\frac{1}{12}+\frac{1}{20}+...+\frac{1}{132}\)
\(\frac{15}{16}:x=\frac{1}{1.2}+\frac{1}{2.3}+\frac{1}{3.4}+\frac{1}{4.5}+...+\frac{1}{11.12}\)
\(\frac{15}{16}:x=1-\frac{1}{2}+\frac{1}{2}-\frac{1}{3}+\frac{1}{3}-\frac{1}{4}+\frac{1}{4}-\frac{1}{5}+...+\frac{1}{11}-\frac{1}{12}\)
\(\frac{15}{16}:x=1-\frac{1}{12}\)
\(\frac{15}{16}:x=\frac{11}{12}\)
\(x=\frac{15}{16}:\frac{11}{12}\)
\(x=\frac{180}{176}\)
Đúng thì like nha
Tìm x biết \(\left(\frac{1}{2}+\frac{1}{4}+\frac{1}{8}+\frac{1}{16}\right)\div x=\frac{1}{2}+\frac{1}{6}+\frac{1}{12}+\frac{1}{20}+...+\frac{1}{132}.\)
\(\left(\frac{1}{2}+\frac{1}{4}+\frac{1}{8}+\frac{1}{16}\right):x=\frac{1}{2}+\frac{1}{6}+....+\frac{1}{32}\)
\(\left(\frac{8}{16}+\frac{4}{16}+\frac{2}{16}+\frac{1}{16}\right):x=\frac{1}{1\times2}+\frac{1}{2\times3}+.....+\frac{1}{11\times12}\)
\(\frac{15}{16}:x=\frac{1}{1}-\frac{1}{2}+\frac{1}{2}-....-\frac{1}{12}\)
\(\frac{15}{16}:x=1-\frac{1}{12}\)
\(\frac{15}{16}:x=\frac{11}{12}\)
\(x=\frac{15}{16}:\frac{11}{12}\)
\(x=\frac{45}{44}\)
Tính \(A=\frac{1}{2}+\frac{1}{4}+\frac{1}{8}+\frac{1}{16}\)
2 x A = \(1+\frac{1}{2}+\frac{1}{4}+\frac{1}{8}\)
2 x A - A = A = \(1-\frac{1}{16}=\frac{15}{16}\)
Tính \(B=\frac{1}{2}+\frac{1}{6}+\frac{1}{12}+...+\frac{1}{132}=\frac{1}{1\times2}+\frac{1}{2\times3}+\frac{1}{3\times4}+....+\frac{1}{11\times12}\)
\(B=\frac{1}{1}-\frac{1}{2}+\frac{1}{2}-\frac{1}{3}+...+\frac{1}{11}-\frac{1}{12}=\frac{1}{1}-\frac{1}{12}=\frac{11}{12}\)
Ta có: \(\frac{15}{16}:x=\frac{11}{12}\Rightarrow x=\frac{15}{16}:\frac{11}{12}=\frac{15}{16}\times\frac{12}{11}=\frac{45}{44}\)
Vậy...
Tìm số tự nhiên x biết
\(\frac{1}{2}+\frac{1}{6}+\frac{1}{12}+\frac{1}{20}+...+\frac{1}{x.\left(x+1\right)}=\frac{2008}{2009}\)
Các bạn giải cụ thể cho mình nhé .
\(\frac{1}{1.2}+\frac{1}{2.3}+\frac{1}{3.4}+...+\frac{1}{x\left(x+1\right)}=\frac{2008}{2009
}\)
\(1-\frac{1}{2}+\frac{1}{2}-\frac{1}{3}+\frac{1}{3}-\frac{1}{4}+...+\frac{1}{x}-\frac{1}{x+1}=\frac{2008}{2009}\)
\(1-\frac{1}{x+1}=\frac{2008}{2009}\)
\(\frac{x+1-1}{x+1}=\frac{2008}{2009}\)
\(\frac{x}{x+1}=\frac{2008}{2009}\)
\(2009x=2008\left(x+1\right)\)
\(2009x=2008x+2008\)
\(2009x-2008x=2008\)
\(x=2008\)
Vậy x=2008
Ta có
1/x.(x+1) =2008-1/1.2-1/2.3-....
tự làm nhé!!
=> \(\frac{1}{1.2}\) + \(\frac{1}{2.3}\) + \(\frac{1}{3.4}\) + \(\frac{1}{4.5}\) +...+\(\frac{1}{x\left(x+1\right)}\) = \(\frac{2008}{2009}\)
=> \(\frac{1}{1}\) - \(\frac{1}{2}\) + \(\frac{1}{2}\) - \(\frac{1}{3}\) + \(\frac{1}{3}\) - \(\frac{1}{4}\) +...+ \(\frac{1}{x}\) - \(\frac{1}{x+1}\) = \(\frac{2008}{2009}\)
=> \(\frac{1}{1}\) - \(\frac{1}{x+1}\) = \(\frac{2008}{2009}\) => \(\frac{1}{x+1}\) = \(\frac{1}{1}\) - \(\frac{2008}{2009}\) = \(\frac{1}{2009}\) => x+1=2009 => x=2008. Vậy x=2008.
Giúp tớ giải mấy bài này với:
Tìm x:
a,\(\frac{1}{3}.x+\frac{2}{5}.\left(x+1\right)=0\)
b,\(x.25\%.x=0,5\)
Tìm số nguyên x và y:
a,\(\frac{6}{2.x+1}=\frac{2}{7}\)
b,\(\frac{x+46}{20}=x\frac{2}{5}\)(\(x\frac{2}{5}\)là hỗn số)
c,\(\frac{24}{7.x-3}=\frac{-4}{25}\)
d,\(\frac{4}{x-6}=\frac{y}{24}=\frac{-12}{18}\)
e,\(y\frac{5}{y}=\frac{86}{y}\)(\(y\frac{5}{y}\)là hỗn số)
Mong các bạn giúp mình nha!!!Các bạn làm được bài nài thi làm, nhanh nha.
Giúp tớ giải mấy bài này với:
Tìm x:
a,\(\frac{1}{3}.x+\frac{2}{5}.\left(x+1\right)=0\)
b,\(x.25\%.x=0,5\)
Tìm số nguyên x và y:
a,\(\frac{6}{2.x+1}=\frac{2}{7}\)
b,\(\frac{x+46}{20}=x\frac{2}{5}\)(\(x\frac{2}{5}\)là hỗn số)
c,\(\frac{24}{7.x-3}=\frac{-4}{25}\)
d,\(\frac{4}{x-6}=\frac{y}{24}=\frac{-12}{18}\)
e,\(y\frac{5}{y}=\frac{86}{y}\)(\(y\frac{5}{y}\)là hỗn số)
Mong các bạn giúp mình nha!!!Các bạn làm được bài nài thi làm, nhanh nha.
Giúp mình với các bạn ơi!!!!!!!!!!!!!!!!!!!!!!!!!!!!
Giúp tớ giải mấy bài này với:
Tìm x:
a,\(\frac{1}{3}.x+\frac{2}{5}.\left(x+1\right)=0\)
b,\(x.25\%.x=0,5\)
Tìm số nguyên x và y:
a,\(\frac{6}{2.x+1}=\frac{2}{7}\)
b,\(\frac{x+46}{20}=x\frac{2}{5}\)(\(x\frac{2}{5}\)là hỗn số)
c,\(\frac{24}{7.x-3}=\frac{-4}{25}\)
d,\(\frac{4}{x-6}=\frac{y}{24}=\frac{-12}{18}\)
e,\(y\frac{5}{y}=\frac{86}{y}\)(\(y\frac{5}{y}\)là hỗn số)
Mong các bạn giúp mình nha!!!Các bạn làm được bài nài thi làm, nhanh nha.
1) \(\frac{24}{-12}=\frac{x}{5}=\frac{-y}{3}\)Tìm x và y
2) \(\frac{1}{3}+\frac{-2}{5}+\frac{1}{6}+\frac{-5}{25}\le\frac{x}{10}< \frac{-3}{4}+\frac{4}{14}+\frac{-2}{8}+\frac{-3}{5}+\frac{5}{7}\)Tìm x
3) \(\frac{8.x+18}{2.x+6}\)Tìm x
1 . Tìm \(x\)
\(\left(\frac{1}{2}+\frac{1}{4}+\frac{1}{8}+\frac{1}{16}\right)\div x=\frac{1}{2}+\frac{1}{6}+\frac{1}{12}+...+\frac{1}{132}\)
+ \(A=\frac{1}{2}+\frac{1}{4}+\frac{1}{6}+\frac{1}{8}\)
=> \(2A=1+\frac{1}{2}+\frac{1}{4}+\frac{1}{8}\)
=> \(A=2A-A=1-\frac{1}{16}=\frac{15}{16}\)
+ \(B=\frac{1}{1x2}+\frac{1}{2x3}+\frac{1}{3x4}+...+\frac{1}{11x12}\)
\(B=\frac{2-1}{1x2}+\frac{3-2}{2x3}+\frac{4-3}{3x4}+...+\frac{12-11}{11x12}\)
\(B=1-\frac{1}{2}+\frac{1}{2}-\frac{1}{3}+\frac{1}{3}-\frac{1}{4}+...+\frac{1}{11}-\frac{1}{12}\)
\(B=1-\frac{1}{12}=\frac{11}{12}\)
\(A:x=B\Rightarrow x=A:B=\frac{15}{16}:\frac{11}{12}=\frac{15}{16}x\frac{12}{11}=\frac{45}{44}=1\frac{1}{44}\)