Bài 1: Tính hợp lý. (nếu có thể)
A= 1/10+1/40+1/88+1/154+1/238+1/340
B=2 +1/547 . 3/211 - 546/547 - 4/547.211
D= 1/3+1/6+1/12+1/24+1/48
E= 1/2 - 1/4 + 1/8 - 1/16 +...+ 1/2048
F= 0,5 - 1/3 - 0,4 -5/7 - 1/6 + 4/35 - 1/41
D= 1/3 +1/6 +1/12 +1/24 +1/48 + 1/96
E= 1/2 - 1/4 + 1/8 - 1/16 +...+ 1/2048
F= -0,5 -1/3 - 0,4 - 5/7 - 1/6 + 4/35 - 1/41
Ai đó giúp mik vớiiiii
\(a,\frac{3}{4}-x=1\) \(b,x+4=\frac{1}{5}\) \(c,x-\frac{1}{5}=2\)
\(d,x+\frac{5}{3}=\frac{1}{81}\) \(e,x-\frac{10}{3}=\frac{7}{15}.\frac{3}{5}\) \(g,x+\frac{3}{22}=\frac{27}{121}.\frac{11}{9}\)
\(h,1-x=\frac{49}{65}.\frac{5}{7}\) \(i,\frac{8}{23}.\frac{46}{24}-x=\frac{1}{3}\) \(k,\frac{62}{7}.x=\frac{29}{9}:\frac{3}{56}\)
Tìm số nguyên x, y biết:
a, \(\dfrac{-1}{5}\)≤ \(\dfrac{x}{8}\)≤ \(\dfrac{1}{4}\)
b, \(\dfrac{4}{x-6}\)= \(\dfrac{y}{24}\)= \(\dfrac{-12}{18}\)
c, \(\dfrac{x+46}{20}\)=x \(\dfrac{2}{5}\)
\(a,15\frac{3}{13}-\left(3\frac{4}{7}+8\frac{3}{13}\right)\)
\(b,\left(7\frac{4}{9}+4\frac{7}{11}\right)-3\frac{4}{9}\)
\(c,\frac{-7}{9}.\frac{4}{11}+\frac{-7}{9}.\frac{7}{11}+5\frac{7}{9}\)
\(d,50\%.1\frac{1}{3}.10.\frac{7}{35}.0,75\)
\(e,\frac{3}{1.4}+\frac{3}{4.7}+\frac{3}{7.10}+....+\frac{3}{40.43}\)
Tìm x, biết:
a) \(\frac{x}{5}-\frac{x}{6}=\frac{3}{10}\)
b) \(-1\frac{5}{27}-\left(3x-\frac{7}{9}\right)^3=-\frac{24}{27}\)
-1\(\dfrac{5}{27}\)-(3x-\(\dfrac{7}{9}\))3=-\(\dfrac{24}{27}\)
a)\(\left(\dfrac{17}{10}+7-8,7\right)\div\left(\dfrac{23}{4}-\dfrac{11}{4}+\dfrac{9}{25}\right)\times\left(12,98\times0,25\right)+12,5\)
b)\(1\dfrac{2}{24}\times5\dfrac{2}{5}\times2\times3\dfrac{7}{9}\times2\times\dfrac{2}{17}\)
Tính nhanh:
a)\(\frac{44\cdot\cdot66+34\cdot44}{3+7+11+...+79}\)
b)\(\frac{1+2+3+...+200}{6+8+10+...+34}\)