\(\frac{\text{2181 . 729 + 234 . 81 . 27}}{\text{ 3^2. 9^2. 234 + 18 . 54 . 162 . 9 + 723 . 729}}\)
= \(\frac{\text{2181 . 729 + 234 . 3 . 81 . 9 }}{\text{ 9 . 81 . 234 + 18 . 54 . 2 . 81 . 9 + 723 . 729 }}\)
= \(\frac{\text{2181 . 729 + 702 . 729 }}{\text{ 729 . 234 + 1944 . 729 + 723 . 729 }}\)
= \(\frac{\text{729 . (2181 + 702) }}{\text{ 729 . (234 + 1944 + 723) }}\)
= \(\frac{\text{729 . 2883 }}{\text{ 729 . 2901 }}\)
= \(\frac{2883}{2901}\)
= \(\frac{961}{967}\)
Tính \(\dfrac{2181.729+243.81.27}{3^2.9^2.234+18.54.162.9+723.729}\)
Tính tổng:
B=\(\frac{1}{2.9}+\frac{1}{9.7}+\frac{1}{7.19}+........+\frac{1}{252.504}\)
C = 2181.729+243.81.27 và D=243.32.92+100+98+96+...+2-1-3-...-95-97
F=49/2.9+49/9.16+49/16.23+...+49/65.72
G=3/1.3+3/3.5+3/5.7+..+3/47.49
Chứng Minh Rằng
a) \(\frac{1}{2}-\frac{1}{4}+\frac{1}{8}-\frac{1}{16}+\frac{1}{32}-\frac{1}{64}< \frac{1}{3}\)
b) \(\frac{1}{3}-\frac{2}{3^2}+\frac{3}{3^3}-\frac{4}{3^4}+.....+\frac{99}{3^{99}}-\frac{100}{3^{100}}< \frac{3}{16}\)
Chứng minh rằng: a)\(\frac{1}{2}-\frac{1}{4}+\frac{1}{8}-\frac{1}{16}+\frac{1}{32}-\frac{1}{64}< \frac{1}{3}\)
b)\(\frac{1}{3}-\frac{2}{3^2}+\frac{3}{3^3}-\frac{4}{3^4}+...+\frac{99}{3^{99}}-\frac{100}{3^{100}}< \frac{3}{16}\)
Nhanh lên nhé! Mk đang cần gấp.
Tính nhanh
\(\frac{\frac{2}{5}+\frac{2}{7}+\frac{2}{9}+\frac{2}{11}+\frac{2}{13}}{\frac{3}{5}+\frac{3}{7}+\frac{3}{9}+\frac{3}{11}+\frac{3}{13}}+\frac{15151515}{45454545}\)
Bài 1: Tính(hợp lý nếu có thể) a) \(6\frac{5}{7}-\left(1\frac{3}{4}+2\frac{5}{7}\right)\) b) \(7\frac{5}{9}-\left(2\frac{3}{4}+3\frac{5}{9}\right)\) c) \(\frac{-3}{5}.\frac{5}{7}+\frac{-3}{5}.\frac{3}{7}+\frac{-3}{5}.\frac{6}{7}\) d) \(\frac{1}{3}.\frac{4}{5}+\frac{1}{3}.\frac{6}{5}-\frac{4}{3}\)
a=1+\frac{1}{3}+\frac{1}{3^{2}}+\frac{1}{3^{3}}+...+\frac{1}{3^{99}}+\frac{1}{3^{100}}