\(B=\dfrac{1}{77}\cdot7^4\cdot11^2\cdot77^5\cdot\dfrac{1}{7^4}:\left(7^3\cdot11^6\right)\)
\(=\dfrac{77^4\cdot11^2\cdot7^4}{7^4}\cdot\dfrac{1}{7^3\cdot11^6}=\dfrac{77^4}{11^4}=7^4\)
\(B=\dfrac{1}{77}\cdot7^4\cdot11^2\cdot77^5\cdot\dfrac{1}{7^4}:\left(7^3\cdot11^6\right)\)
\(=\dfrac{77^4\cdot11^2\cdot7^4}{7^4}\cdot\dfrac{1}{7^3\cdot11^6}=\dfrac{77^4}{11^4}=7^4\)
Thực hiện phép tính:\(\left(-\dfrac{1}{2}\right)-\left(-\dfrac{3}{5}\right)+\left(-\dfrac{1}{9}\right)+\dfrac{1}{71}-\left(-\dfrac{2}{7}\right)+\dfrac{4}{35}-\dfrac{7}{18}\)
Thực hiện phép tính:
\(A=\dfrac{2^{12}.3^5-4^6.9^2}{\left(2^2.3\right)^6+8^4.3^5}-\dfrac{5^{10}.7^3-25^5.49^2}{\left(125.7\right)^3+5^9.14^3}\)
\(B=\dfrac{1-\dfrac{1}{\sqrt{49}}+\dfrac{1}{49}-\dfrac{1}{\left(7\sqrt{7}\right)^2}}{\dfrac{\sqrt{64}}{2}-\dfrac{4}{7}+\dfrac{2^2}{7^2}-\dfrac{4}{343}}\)
thực hiện phép tính: \(\left(5+\dfrac{1}{5}-\dfrac{2}{9}\right)-\left(2-\dfrac{1}{23}-2\dfrac{3}{35}+\dfrac{5}{6}\right)-\left(8+\dfrac{2}{7}-\dfrac{1}{18}\right)\)
Tính :
a)\(\left(2+\dfrac{4}{5}-\dfrac{7}{12}\right).\left(\dfrac{6}{7}-\dfrac{2}{5}\right)^2\)
b) \(\left(2\dfrac{1}{2}+3,5\right):\left(-4\dfrac{1}{6}+3\dfrac{1}{7}\right)+7,5\)
Thực hiện phép tính : A = \(\dfrac{\left(\dfrac{-3}{10}+\dfrac{4}{15}+\dfrac{7}{20}\right).\left(\dfrac{-5}{19}\right)}{\left[\dfrac{1}{14}+\dfrac{1}{7}-\left(\dfrac{-3}{35}\right).\left(-1\dfrac{1}{3}\right)\right]}:\dfrac{5}{24}\)
tính hợp lý nếu có thể
a)\(\left(\dfrac{-6}{11}\right).\dfrac{7}{10}.\left(\dfrac{11}{-6}\right).\left(-20\right)\)
b)\(\left(-1\dfrac{1}{2}\right):\dfrac{3}{4}.\left(-4\dfrac{1}{2}\right)\)
Bài 1: Thực hiện phép tính:
\(\sqrt{25}\)x\(\left(0,4-1\dfrac{1}{12}\right)\):\(\left[\left(-2\right)^3x\dfrac{11}{8}\right]\)
Tìm x:
a)\(5\dfrac{4}{7}:\left\{x:1,3+8,4.\dfrac{6}{7}.\left[6-\dfrac{\left(2,3+5:6,25\right).7}{8.0,0125+6,9}\right]\right\}=1\dfrac{1}{14}\)
b)\(\left|3x-2\right|+\left|2x-1\right|=4\)
\(\left[18\dfrac{1}{6}-\left(0,06:7\dfrac{1}{2}+3\dfrac{2}{5}\cdot0,38\right)\right]:\left(19-2\dfrac{2}{3}\cdot4\dfrac{3}{4}\right).Tính\)