Có: \(A-B=\frac{9}{11^4}+\frac{5}{11^5}-\left(\frac{5}{11^4}+\frac{9}{11^5}\right)\)
\(=9\left(\frac{1}{11^4}-\frac{1}{11^5}\right)-\left[5\left(\frac{1}{11^4}-\frac{1}{11^5}\right)\right]\)
\(=4\left(\frac{1}{11^4}-\frac{1}{11^5}\right)\)>0
Vậy A>B.
Tính giá trị của biểu thức:
a)\(A=\) \(\frac{\frac{1}{3}+\frac{1}{9}-\frac{1}{27}}{\frac{5}{3}+\frac{5}{9}-\frac{5}{27}}\)
b)\(B=\frac{\frac{2}{3}-\frac{1}{4}+\frac{5}{11}}{\frac{5}{12}+1-\frac{7}{11}}\)
3,Tính hợp lý
a,\(\frac{3}{7}\cdot\frac{4}{9}+\frac{3}{7}\cdot\frac{5}{9}+\frac{5}{14}\)
b,\(\frac{-11}{23}\cdot\frac{6}{7}+\frac{8}{9}\cdot\frac{-11}{23}-\frac{1}{23}\)
Giúp mình nhé!!!
Tính
\(\frac{5-\frac{5}{3}-\frac{5}{9}-\frac{5}{27}}{8-\frac{8}{3}-\frac{8}{9}-\frac{8}{27}}\):\(\frac{15-\frac{15}{11}+\frac{15}{121}}{16-\frac{16}{11}+\frac{16}{121}}\)
các bạn có thể giúp mình bài này không
\(B=\frac{\frac{1}{9}-\frac{1}{7}-\frac{1}{11}}{\frac{1}{9}-\frac{1}{7}-\frac{1}{11}}+\frac{\frac{3}{5}-\frac{3}{25}-\frac{3}{125}-\frac{3}{625}}{\frac{4}{5}-\frac{4}{25}-\frac{4}{125}-\frac{4}{625}}\)
Thực hiện các phép tính:
a) \(\frac{5}{9}:\frac{13}{7}+\frac{5}{9}:\frac{13}{9}-1\frac{2}{3}\)
b) \(\left(15-6\frac{13}{18}\right):11\frac{1}{27}-2\frac{1}{8}:1\frac{11}{40}\)
Tính nhanh
\(\frac{\frac{2}{5}+\frac{2}{7}+\frac{2}{9}+\frac{2}{11}+\frac{2}{13}}{\frac{3}{5}+\frac{3}{7}+\frac{3}{9}+\frac{3}{11}+\frac{3}{13}}+\frac{15151515}{45454545}\)
1.tính các biểu thức sau bằng một cách hợp lí
a.\(\frac{108}{119}.\frac{107}{211}+\frac{108}{119}.\frac{104}{211}\)
b.\(\frac{15}{19}.\frac{27}{33}+\frac{15}{19}.\frac{19}{33}-\frac{15}{19}.\frac{13}{33}\)
c.\(\frac{-4}{5}.\frac{13}{10}+\frac{-4}{5}.\frac{7}{10}-\frac{-4}{5}\)
d.\(\frac{\frac{-2}{7}-\frac{-2}{15}+\frac{-2}{39}}{\frac{5}{7}-\frac{5}{15}+\frac{5}{39}}\)
e.\(\frac{3}{5}.\frac{15}{7}-\frac{15}{7}.\frac{8}{5}\)
f.\(\frac{2}{3}+\frac{1}{3}.\left(\frac{-4}{9}+\frac{5}{6}\right):\frac{7}{12}\)
h.\(\frac{\frac{3}{5}+\frac{3}{7}-\frac{3}{11}}{\frac{4}{5}+\frac{4}{7}-\frac{4}{11}}\)
g.\(\frac{3}{-4}+\frac{2}{7}+\frac{-1}{4}+\frac{5}{7}+\frac{21}{22}.\frac{66}{7}\)
k.\(\frac{27.18+27.103-120.27}{15.33+33.12}\)
l.\(\frac{\frac{2}{5}+\frac{2}{7}-\frac{2}{9}-\frac{2}{11}}{\frac{4}{5}+\frac{4}{7}-\frac{4}{9}-\frac{4}{11}}\)
Bài 1: rút gọn các phân số sau:
a) \(\frac{3^{10}.\left(-5\right)^{21}}{\left(-5\right)^{20}.3^{12}}\)
b) \(\frac{-11^5.13^7}{11^5.13^8}\)
c) \(\frac{2^{10}.3^{10}-2^{10}.3^9}{2^9.3^{10}}\)
d) \(\frac{5^{11}.7^{12}+5^{11}.7^{11}}{5^{12}.7^{12}+9.5^{11}.7^{11}}\)
Bài 1: Tính (hợp lý nếu có thể)
a) \(\frac{8}{40}+\frac{-4}{20}-\frac{3}{5}\)
b) \(\frac{-7}{12}+\frac{-2}{12}-\frac{-3}{36}\)
c) \((\frac{1}{6}+\frac{-4}{13})-(\frac{-17}{6}-\frac{30}{13})\)
d) \(-\frac{-5}{4}+\frac{7}{4}-\frac{-11}{7}+\frac{2}{7}\)
e) \(-\frac{1}{8}+\frac{-7}{9}+\frac{-7}{8}+\frac{6}{7}+\frac{2}{14}\)
f) \(\frac{-2}{9}-\frac{11}{-9}+\frac{5}{7}-\frac{-6}{-7}\)
