Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
\(\frac{2013}{2014}:1\frac{1}{7}+\frac{2013}{2014}:\frac{11}{19}+\frac{2013}{2014}:\frac{11}{5}\)
= \(\frac{2013}{2014}:\left(1\frac{1}{7}+\frac{11}{19}+\frac{11}{5}\right)\)
= \(\frac{2013}{2014}:\left(\frac{8}{7}+\frac{11}{19}+\frac{11}{5}\right)\)
= \(\frac{2013}{2014}:\frac{2608}{665}\)
= \(0,2548...\)
= 2011 x 2012 + 2011 x 2 / 2013 x 2014 - 2014 x 2
= 2011 x 2014 / 2014 x 2011 = 1
k mk nha
$\frac{\frac{2010}{2011}}{\frac{2012}{2013}}+\frac{\frac{2011}{2012}}{\frac{2013}{2014}}+\frac{\frac{2012}{2013}}{\frac{2014}{2015}}$
$\frac{\frac{2010}{2011}}{\frac{2012}{2013}}+\frac{\frac{2011}{2012}}{\frac{2013}{2014}}+\frac{\frac{2012}{2013}}{\frac{2014}{2015}}$
$\frac{\frac{2010+2011+2012}{2011+2012+2013}}{\frac{2012+2013+2014}{2013+2014+2015}}$
$\frac{\frac{2010}{2011}+\frac{2011}{2012}+\frac{2012}{2013}}{\frac{2012+2013+2014}{2013+2014+2015}}$
$\frac{\frac{2010+2011+2012}{2011+2012+2013}}{\frac{2012}{2013}+\frac{2013}{2014}+\frac{2014}{2015}}$
Đặt phân thức trên là D
=> D=(1+1+1+1+...+1+2013/2+2012/3+...+2/2013+1/2014)/(1/2+1/3+1/4+...+1/2014)
=> D=(1+2013/2+1+2012/3+1+2011/4+...+1+2/2013+1+1/2014+1)/(1/2+1/3+1/4+1/5+...+1/2014)
=> D=(2015/2+2015/3+2015/4+...+2015/2013+2015/2014+1)/(1/2+1/3+1/4+...+1/2014)
=> D=[2015*(1/2+1/3+1/4+1/5+....+1/2014)]/(1/2+1/3+1/4+1/5+...+1/2014)
=> D=2015
( 1999 x 1998 + 1998 x 1997 ) x \(\left(1+\frac{1}{2}:1\frac{1}{2}-1\frac{1}{3}\right)\)
= ( 1999 x 1998 + 1998 x 1997 ) x \(\left(1+\frac{1}{2}:\frac{3}{2}-\frac{4}{3}\right)\)
= ( 1999 x 1998 + 1998 x 1997 ) x \(\left(1+\frac{1}{3}-\frac{4}{3}\right)\)
= ( 1999 x 1998 + 1998 x 1997 ) x 0
= 0