Ta có: \(A=\frac{10^5+3}{10^5-7}=\frac{\left(10^5-7\right)+10}{10^5-7}=1+\frac{10}{10^5-7}\)
\(B=\frac{10^5+4}{10^5-6}=\frac{\left(10^5-6\right)+10}{10^5-6}=1+\frac{10}{10^5-6}\)
Vì \(\frac{10}{10^5-7}>\frac{10}{10^5-6}\), do đó \(A>B\)
Ta có: \(A=\frac{10^5+3}{10^5-7}=\frac{\left(10^5-7\right)+10}{10^5-7}=1+\frac{10}{10^5-7}\)
\(B=\frac{10^5+4}{10^5-6}=\frac{\left(10^5-6\right)+10}{10^5-6}=1+\frac{10}{10^5-6}\)
Vì \(\frac{10}{10^5-7}>\frac{10}{10^5-6}\), do đó \(A>B\)
\(\frac{10+\frac{9}{2}+\frac{8}{3}+\frac{7}{4}+ \frac{6}{5}+\frac{5}{6}+\frac{4}{7}+\frac{3}{8}+\frac{2}{9}+\frac{1}{10}}{\frac{1}{2}+\frac{1}{3}+\frac{1}{4}+...+\frac{1}{10}+\frac{1}{11}}\)
1.tính giá trị biểu thức sau một cách hợp lí nếu có
a)\(\frac{1}{3}.\frac{4}{5}+\frac{1}{3}.\frac{6}{5}-\frac{5}{3}\)
b)\(\frac{4}{19}.\frac{-3}{7}+\frac{-3}{7}.\frac{15}{19}+\frac{5}{7}\)
c)\(\frac{6}{7}.\frac{10}{9}+\frac{1}{7}.\frac{10}{9}-\frac{8}{9}\)
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) \(\frac{5^{11}.7^{12}+5^{11}.7^{11}}{5^{12}.7^{12}+9.5^{11}.7^{11}}\)
Biết \(2-\frac{3}{4-\frac{5}{6-\frac{7}{8-\frac{9}{10}}}}=2-\frac{3}{4-\frac{5}{x}}\). Tìm x.
so sanh hai phân số A =\(\frac{10^{29}+5}{10^{29}-2}\)và B =\(\frac{10^{29}}{10^{29}-7}\)
So sánh A= \(\dfrac{10^{2023}+5}{10^{2022}+5}\) và B=\(\dfrac{10^{2022}+5}{10^{2021}+5}\)
So sánh A= \(\dfrac{10^{2023}+5}{10^{2022}+5}\) và B= \(\dfrac{10^{2022}+5}{10^{2022}+5}\)
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.\(\frac{\frac{2}{5}+\frac{2}{7}-\frac{2}{9}-\frac{2}{11}}{\frac{4}{5}+\frac{4}{7}-\frac{4}{9}-\frac{4}{11}}\)
So sánh giá trị 2 biểu thức:
A=\(\dfrac{1+7+7^2+...+7^9}{1+7+7^2+...+7^{10}}\) và B=\(\dfrac{1+5+5^2+...+5^9}{1+5+5^2+...+5^{10}}\)
Mí bạn giúp tớ điii
giải rõ hộ nha :3