a: =31/9+31/6=155/18
b: =113/14-45/7=23/7
c: =7-3-6/7=4-6/7=24/7
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§3. Các phép toán tập hợp
Các câu hỏi tương tự
Tính bằng cách hợp lí :
a , dfrac{1}{15}+dfrac{9}{10}+dfrac{14}{15}-dfrac{11}{9}-dfrac{20}{10}+dfrac{1}{157}
b , dfrac{1}{5}-dfrac{-1}{3}+dfrac{-1}{5}-dfrac{2}{6}
c , dfrac{2}{1times3}+dfrac{2}{3times5}+...+dfrac{2}{2015times2017}
d , dfrac{5}{1times3}+dfrac{5}{3times5}+...+dfrac{5}{2015times2017}
e , dfrac{1}{1times2}+dfrac{1}{3times4}+...+dfrac{1}{2016times2017}
Đọc tiếp
Tính bằng cách hợp lí :
a , \(\dfrac{1}{15}+\dfrac{9}{10}+\dfrac{14}{15}-\dfrac{11}{9}-\dfrac{20}{10}+\dfrac{1}{157}\)
b , \(\dfrac{1}{5}-\dfrac{-1}{3}+\dfrac{-1}{5}-\dfrac{2}{6}\)
c , \(\dfrac{2}{1\times3}+\dfrac{2}{3\times5}+...+\dfrac{2}{2015\times2017}\)
d , \(\dfrac{5}{1\times3}+\dfrac{5}{3\times5}+...+\dfrac{5}{2015\times2017}\)
e , \(\dfrac{1}{1\times2}+\dfrac{1}{3\times4}+...+\dfrac{1}{2016\times2017}\)
Cho A= \(1+\dfrac{1}{2}+\dfrac{1}{3}+\dfrac{1}{4}+...+\dfrac{1}{4026}\) , B = \(1+\dfrac{1}{3}+\dfrac{1}{5}+\dfrac{1}{7}+....+\dfrac{1}{4025}\). So sánh \(\dfrac{A}{B}\) với \(1\dfrac{2013}{2014}\)
\(A=\dfrac{2^{12}\cdot3^5-4^6\cdot9^2}{\left(2^2\cdot3\right)^6+8^4\cdot3^5}-\dfrac{5^{10}\cdot7^3-25^5\cdot49^2}{\left(125\cdot7\right)^3+5^9\cdot14^3}\)
Cho biểu thức:
A= (\(2-\dfrac{\sqrt{x}-1}{2\sqrt{x}-3}\)) : (\(\dfrac{6\sqrt{x}+1}{2x-\sqrt{x}-3}+\dfrac{\sqrt{x}}{\sqrt{x}+1}\))
a) Rút gọn A
b) Tính A khi x = \(\dfrac{3-2\sqrt{2}}{4}\)
SO SÁNH
Đặt A= \(\dfrac{3}{1^2.2^2}+\dfrac{5}{2^2.3^2}+\dfrac{7}{3^2.4^2}+...+\dfrac{39}{19^2-20^2}với1\)
Tính:
\(\dfrac{1}{2}+\dfrac{1}{3}+\dfrac{1}{5}+\dfrac{1}{7}\)
Lẹ nha mấy chế!!!~.~
\((\)\(\dfrac{-4}{5}\)).(-\(\dfrac{-25}{8}\))
\(\dfrac{5}{-14}\).(-\(\dfrac{7}{10}\))
\(B=\left|157\dfrac{13}{27}-273\dfrac{7}{19}\right|-96\dfrac{14}{27}+15\dfrac{12}{19}\)\(B=\left|157\dfrac{13}{27}-273\dfrac{7}{19}\right|-96\dfrac{14}{27}+15\dfrac{12}{19}\)
từ lúc nãy giờ mình giúp các bn giờ giúp lại mình với
\(\dfrac{1+3^4+3^8+3^{12}}{1+3^2+3^4+3^6+3^8+3^{10}+3^{12}+3^{14}}\)