\(\left(\dfrac{3}{29}-\dfrac{1}{5}\right)\cdot\dfrac{23}{9}=\left(\dfrac{15}{145}-\dfrac{29}{145}\right)\cdot\dfrac{23}{9}=-\dfrac{14}{145}\cdot\dfrac{23}{9}=-\dfrac{322}{1305}\)
\(\left[\left(\dfrac{-3}{8}+\dfrac{11}{23}\right):\dfrac{5}{9}+\left(\dfrac{-5}{8}+\dfrac{12}{23}\right):\dfrac{5}{9}\right].\dfrac{11}{235}\)
Thực hiện phép tính (bằng cách hợp lý nếu có thể)
a) \(1\dfrac{4}{23}+\dfrac{5}{21}-\dfrac{4}{23}+0,5+\dfrac{16}{21}\)
b) \(\dfrac{3}{7}.19\dfrac{1}{3}-\dfrac{3}{7}.33\dfrac{1}{3}\)
c) \(9.\left(-\dfrac{1}{3}\right)^3+\dfrac{1}{3}\)
d) \(15\dfrac{1}{4}:\left(-\dfrac{5}{7}\right)-25\dfrac{1}{4}\left(-\dfrac{5}{7}\right)\)
Tính giá trị của các biểu thức sau 1) \(A=1+2+2^2+...+2^{2015}\) 2) \(B=\left(\dfrac{1}{4}-1\right)\cdot\left(\dfrac{1}{9}-1\right)\cdot\left(\dfrac{1}{16}-1\right)\cdot\cdot\cdot\cdot\cdot\left(\dfrac{1}{400}-1\right)\) 3) \(C=\left(\dfrac{1}{4\cdot9}+\dfrac{1}{9\cdot14}+\dfrac{1}{14\cdot19}+...+\dfrac{1}{44\cdot49}\right)\cdot\dfrac{1-3-5-7-...-49}{89}\) 4) \(D=\dfrac{2^{12}\cdot3^5-4^6\cdot9^2}{\left(2^2\cdot3\right)^6+8^4\cdot3^5}-\dfrac{5^{10}\cdot7^3-25^5\cdot49^2}{\left(125\cdot7\right)^3+5^9\cdot14^3}\) 5) \(E=\dfrac{\dfrac{1}{2003}+\dfrac{1}{2004}-\dfrac{1}{2005}}{\dfrac{5}{2003}+\dfrac{5}{2004}-\dfrac{5}{2005}}-\dfrac{\dfrac{2}{2002}+\dfrac{2}{2003}-\dfrac{2}{2004}}{\dfrac{3}{2002}+\dfrac{3}{2003}-\dfrac{3}{2004}}\) 6) Cho 13+23+...+103=3025 Tính S= 23+43+63+...+203
a) \(4.\left(-\dfrac{1}{2}\right)^3\)\(-2.\left(-\dfrac{1}{2}\right)^2\)+\(3.\left(-\dfrac{1}{2}\right)\)+1
b) \(8.\sqrt{9}\)\(-\sqrt{64}\)
c) \(\sqrt{\dfrac{9}{16}}\)\(+\dfrac{25}{46}\)\(:\dfrac{5}{23}\)\(-\dfrac{7}{4}\)
đung cho 5 sao
b) \(1\dfrac{5}{9}.x=\dfrac{28}{29}\)
c) \(x:(\dfrac{-2}{5})=\dfrac{-15}{16}\)
Tính giá trị của các biểu thức sau
1) \(A=1+2+2^2+...+2^{2015}\)
2) \(B=\left(\dfrac{1}{4}-1\right)\cdot\left(\dfrac{1}{9}-1\right)\cdot\left(\dfrac{1}{16}-1\right)\cdot\cdot\cdot\cdot\cdot\left(\dfrac{1}{400}-1\right)\)
3) \(C=\left(\dfrac{1}{4\cdot9}+\dfrac{1}{9\cdot14}+\dfrac{1}{14\cdot19}+...+\dfrac{1}{44\cdot49}\right)\cdot\dfrac{1-3-5-7-...-49}{89}\)
4) \(D=\dfrac{2^{12}\cdot3^5-4^6\cdot9^2}{\left(2^2\cdot3\right)^6+8^4\cdot3^5}-\dfrac{5^{10}\cdot7^3-25^5\cdot49^2}{\left(125\cdot7\right)^3+5^9\cdot14^3}\)
5) \(E=\dfrac{\dfrac{1}{2003}+\dfrac{1}{2004}-\dfrac{1}{2005}}{\dfrac{5}{2003}+\dfrac{5}{2004}-\dfrac{5}{2005}}-\dfrac{\dfrac{2}{2002}+\dfrac{2}{2003}-\dfrac{2}{2004}}{\dfrac{3}{2002}+\dfrac{3}{2003}-\dfrac{3}{2004}}\)
6) Cho 13+23+...+103=3025
Tính S= 23+43+63+...+203
\(5\dfrac{5}{27}+\dfrac{7}{23}-0,5.\dfrac{5}{27}+\dfrac{16}{23}=\)
\(45\dfrac{1}{6}:\left(\dfrac{-4}{5}\right)-35\dfrac{1}{6}:\left(\dfrac{-4}{5}\right)=\)
\(25.\left(\dfrac{-1}{5}\right)^3+\dfrac{1}{5}-2.\left(\dfrac{-1}{2}\right)^2-\dfrac{1}{2}=\)
\(\left(3,1-2,5\right)-\left(-2,5-3,1\right)=\)
\(\dfrac{3}{8}.\dfrac{7}{5}-\dfrac{7}{5}.\dfrac{1}{8}+\dfrac{13}{20}=\)
CẦN GẤP NGAY VÀ LUÔN :)))))
so sánh các cặp số hữu tỉ sau
a)\(\dfrac{3}{-7}\)và \(\dfrac{-5}{9}\)
b)-0,625 và \(\dfrac{-19}{50}\)
c)\(-2\dfrac{5}{9}\)và \(-\left(\dfrac{-23}{-9}\right)\)
giúp mình với, mik tick cho
\(\left(1\dfrac{4}{23}-\dfrac{5}{21}\right)-\left(\dfrac{4}{23}-\dfrac{3}{4}\right)-\dfrac{16}{21}\)
Thực hiện phét tính B=\(\dfrac{155-\dfrac{10}{7}-\dfrac{5}{11}+\dfrac{5}{23}}{403-\dfrac{26}{7}-\dfrac{13}{11}+\dfrac{13}{23}}+\dfrac{\dfrac{-3}{5}-\dfrac{3}{13}+0,9}{\dfrac{2}{5}+\dfrac{2}{13}-\dfrac{6}{10}}\)
