tìm kiểu gì vậy
tìm kiểu gì vậy
A=\(\frac{1}{1.2}+\frac{1}{2.3}+\frac{1}{3.4}+\frac{1}{4.5}+...+\frac{1}{18.19}+\frac{1}{19.20}\)
Gải giúp mình với nha mik tick cho
\(\frac{x-2}{12}+\frac{x-2}{20}+\frac{x-2}{30}+\frac{x-2}{42}=42^5:\left(2^3.21^6\right)\)
Giúp mk nha!!!!!!
Tìm x, biết:
a)x=\(\frac{-1}{2}+\frac{3}{4}\)
b)\(\frac{x}{5}=\frac{5}{6}+\frac{-19}{30}\)
Tìm x, biết:
a) \(\frac{29}{30}\)-\((\frac{13}{23}\)+x\()\)=\(\frac{7}{69}\)
b) \(\frac{1}{2}\)+\(\frac{1}{6}\)+\(\frac{1}{12}\)+...+\(\frac{1}{x\left(x+1\right)}\)=\(\frac{2011}{2012}\)
BT1; Tính;
a,2:\(\frac{-1}{3}\)+\(\frac{1}{3}\).\(\frac{2}{7}\)+\(\frac{1}{3}\).\(\frac{5}{7}\)
b,9,12+88%-1\(\frac{1}{5}\):\(\frac{1}{10}\)
c,\(\frac{5}{6}\)x+\(\frac{1}{4}\)x=\(\frac{1}{6}\)-\(\frac{5}{4}\)
Cho A=1/1.2 + 1/2.3 + + 1/ 3.4+...+1/49.50 ; B = 1.2+2.3+3.4+4.5+5.6+...+49.50
Tính 50 mủ 2 A – B/17
tính giá trị biểu thức : A= 4/1.2+4/2.3+4/3.4+...4/2014.2015
Chứng minh rằng : \(\frac{5}{6}-\frac{2}{3^2}+\frac{3}{3^3}-\frac{4}{3^4}+...+\frac{99}{3^{99}}-\frac{100}{3^{100}}< \frac{11}{16}\)
\(\frac{1}{2}+\frac{1}{2^2}+\frac{1}{2^3}+...+\frac{1}{2^{99}}+\frac{1}{2^{100}}+\frac{1}{2^{100}}\)
Giúp mk với...