\(A=2007+2008\times2009:2009\times2010-2011=2007+2008\times2010-2011\)(Vì 2009:2009=1)

A=2008+4036080-2011

A=4036077

A=2007+2008x1x2010-2011

A=2007+2008x2010-2011

A=2007+4036080-2011

A=4036077

dài quá

k nha

cảm ơn bạn

A= 4036076

S=1-\(\frac{1}{2}\)+\(\frac{1}{2}\)-\(\frac{1}{3}\)+...+\(\frac{1}{2009}\)-\(\frac{1}{2010}\)

S=1-\(\frac{1}{2010}\)

S=\(\frac{2009}{2010}\)

k nha bn

\(S=\frac{1}{1\times2}+\frac{1}{2\times3}+\frac{1}{3\times4}+...+\frac{1}{2008\times2009}+\frac{1}{2009\times2010}\)

\(=1-\frac{1}{2}+\frac{1}{2}-\frac{1}{3}+\frac{1}{3}-\frac{1}{4}+...+\frac{1}{2008}-\frac{1}{2009}+\frac{1}{2009}-\frac{1}{2010}\)

\(=1-\frac{1}{2010}\)

\(=\frac{2009}{2010}\)

Vậy \(S=\frac{2009}{2010}\)

Học tốt #

s = 1- 1/2+ 1/2- 1/3+ 1/3- 1/4 ......-1/2008- 1/2009+ 1/2009- 1/2010

s =1- 1/2010

s = 2009/2010

\(A=\frac{2009x2010+2000}{2011x2010-2020}=\frac{2009x2010+2000}{2009x2010+2x2010-2020}=\frac{2009x2010+2000}{2009x2010+4020-2020}=\frac{2000}{4020-2020}=\frac{2000}{2000}=1\)

Nhấn đúng cho mk nha!!!!!!!!!!

\(t=\frac{2009.2010+2000}{2011.2010-2020}\)

\(t=\frac{2009.2010+2000}{\left(2009+2\right).2010-2020}\)

\(t=\frac{2009.2010+2000}{2009.2010+2.2010-2020}\)

\(t=\frac{2009.2010+2000}{2009.2010+2000}=1\)

\(q=\frac{\text{2014.2015+2010}}{2016.2015-2020}\)

\(q=\frac{\text{2014.2015+2010}}{\left(2014+2\right).2015-2020}\)

\(q=\frac{\text{2014.2015+2010}}{2014.2015+2.2015-2020}\)

\(q=\frac{\text{2014.2015+2010}}{\text{2014.2015+2010}}=1\)

 \(\frac{2009x2010+20}{2009x2010-1990}\)

=\(\frac{2009x2010+20}{2009x2010+2010-1990}\)

=\(\frac{2009x2010+20}{2009x2010+20}\)

\(\frac{2009+20}{2010-1990}=\frac{2029}{20}=>\frac{2009x2010+20}{2010x2010-1990}=\frac{2029}{20}\)

\(\frac{2009x2010+20}{20102x2010-1990}\)

=\(\frac{2009x2010+20}{2009x2010+2010-1990}\)

=\(\frac{2009x2010+20}{2009x2010+20}\)

= 1

ta có: \(\frac{2008}{2008\cdot2009}=\frac{2008}{2008}\cdot\frac{1}{2009}=1\cdot\frac{1}{2009}\)

\(\frac{2009}{2009\cdot2010}=\frac{2009}{2009}\cdot\frac{1}{2010}=1\cdot\frac{1}{2010}\)

Vì 2009<2010 nên \(\frac{1}{2009}>\frac{1}{2010}nên\frac{2008}{2008\cdot2009}>\frac{2009}{2009\cdot2010}\)

Chúc bạn học tốt!^_^

a)2007/2008

b)2009x2009/2008x2008

bạn giải chi tiết ra nhé giúp mk với

 1999 x (2000+1)-1=1999x2000+1999-1=1999x2000+1998=1

1998+1999x2000=giữ nguyên=1998+1999x2000=1 Vậy kết quả phân số = 1 k cho mình nhé