Violympic toán 7
Các câu hỏi tương tự
Tìm x biết
\(\left(\dfrac{1}{2}+\dfrac{1}{3}+...+\dfrac{1}{2015}+\dfrac{1}{2016}\right)x=\dfrac{2015}{1}+\dfrac{2014}{2}+...+\dfrac{2}{2014}+\dfrac{1}{2015}\)
Tìm x biết \(\dfrac{x+4}{2015}+\dfrac{x+3}{2016}=\dfrac{x+2}{2017}+\dfrac{x+1}{2018}\)
tìm x biết (\(\dfrac{1}{2}\)+\(\dfrac{1}{3}\)+\(\dfrac{1}{4}\)+...+\(\dfrac{1}{2018}\)).x=\(\dfrac{2017}{1}+\dfrac{2016}{2}+\dfrac{2015}{3}+...+\dfrac{2}{2016}+\dfrac{1}{2017}\)
Tìm x , biết ;
\(\dfrac{x+1}{2016}+\dfrac{x+2}{2015}=\dfrac{x+3}{2014}+\dfrac{x+4}{2013}\)
Cho A= \(\dfrac{1}{2015}+\dfrac{2}{2016}+...+\dfrac{2016}{4030}-2016\)
B=\(\dfrac{1}{2015}+\dfrac{1}{2016}+...+\dfrac{1}{4030}\)
CMR \(\dfrac{A}{B}\)\(\varepsilon\)Z
tìm x biết 1\2016:2015x=-1/2015
ai nhanh, ai đúng dc 1 tích
Tìm X \(\dfrac{x-1}{2017}+\dfrac{x-2}{2016}=\dfrac{x-3}{2015}+\dfrac{x-4}{2014}\)
Cho A=\(\left(\dfrac{1}{2}-1\right).\left(\dfrac{1}{3}-1\right).\left(\dfrac{1}{4}-1\right)...\left(\dfrac{1}{2015}-1\right).\left(\dfrac{1}{2016}-1\right).\left(\dfrac{1}{2017}-1\right)\)
B=\(\left(-1\dfrac{1}{2}\right).\left(-1\dfrac{1}{3}\right).\left(-1\dfrac{1}{4}\right)...\left(-1\dfrac{1}{2015}\right).\left(-1\dfrac{1}{2016}\right).\left(-1\dfrac{1}{2017}\right)\)
Tính M=A.B
a, CMR : nếu \(\dfrac{a}{b}=\dfrac{c}{d}\) thì \(\dfrac{5a+3b}{5a-3b}=\dfrac{5c+3d}{5c-3d}\) ( gt các tỉ số đều có nghĩa )
b, tìm x,biết: \(\dfrac{x-1}{2017}+\dfrac{x-2}{2016}+\dfrac{x-3}{2015}=\dfrac{x-4}{2014}\)