tính giá trị các biểu thức A,B,C rồi sắp xếp các kết quả tìm được theo thứ tự nhỏ tới lớn
A=\(\dfrac{2}{3}\)+\(\dfrac{3}{4}\)\(\times\)\(\dfrac{-4}{9}\)
B=2\(\dfrac{3}{11}\)\(\times\)1\(\dfrac{1}{12}\)\(\times\)(-2,2)
C=\((\)\(\dfrac{3}{4}\) - 0,2 \()\) \(\times\)\((\) 0,4 - \(\dfrac{4}{5}\) )
tìm x \(\in\) Q biết rằng
\(\dfrac{11}{12}\) - ( \(\dfrac{2}{5}\) + x ) = \(\dfrac{2}{3}\)
2x \(\times\) ( x - \(\dfrac{1}{7}\) ) = 0
\(\dfrac{3}{4}\) + \(\dfrac{1}{4}\) : x = \(\dfrac{2}{5}\)
\(\dfrac{-7}{2}\times\dfrac{4}{11}+\dfrac{7}{14}\times\dfrac{-7}{2}+\dfrac{13}{2}=\)?
1/ Cho A= \(\dfrac{1}{3}\)-\(\dfrac{2}{3^2}\)+\(\dfrac{3}{3^3}\)-\(\dfrac{4}{3^4}\)+.....+\(\dfrac{99}{3^{99}}\)-\(\dfrac{100}{3^{100}}\) Chứng minh A < \(\dfrac{3}{16}\)
2/ Cho B=(\(\dfrac{1}{2^2}\)-1)(\(\dfrac{1}{3^2}\)-1)....(\(\dfrac{1}{100^2}\)-1) So sánh B và \(\dfrac{-1}{2}\)
thực hiện phép tính
\(l.\dfrac{\dfrac{1}{3}+\dfrac{1}{7}-\dfrac{1}{23}}{\dfrac{2}{3}+\dfrac{2}{7}-\dfrac{2}{23}}\times\dfrac{\dfrac{1}{3}-0.25-0.2}{1\dfrac{1}{6}-0.875-0.7}\)
D = \(\left(-2\right)^3\times\left(\dfrac{3}{4}-0,25\right):\left(2\dfrac{1}{4}-1\dfrac{1}{6}\right)\)
\(\sqrt{\dfrac{4}{25}+|-\dfrac{4}{5}|-\dfrac{9}{5}\times\left(\dfrac{-1}{3}\right)}^2+0,75\)
\(5\times(\dfrac{-5}{2})^2+\dfrac{2}{15}\times\sqrt{\dfrac{9}{4}}-(-2022)^0+|-0,25|\)
\(\dfrac{2\times x}{3\times y}=\dfrac{-1}{3}\)và 2x-3y=7