11+11+1=23

1_1+1_1+1=2_2+ ko

nếu đúng thi k mình nha

= 1 -1 +1 - 1 + 1 = 1

bạn nào giúp mình với

wtf t chịu ơ hớ 

\(\dfrac{-1}{1}\)

B1:

B2:

B3:

(1-1/10)x(1-1/11)x(1-1/12)x(1-1x1/13)=\(\dfrac{9}{10}\)x\(\dfrac{10}{11}\)x\(\dfrac{11}{12}\)x\(\dfrac{12}{13}\)=\(\dfrac{9}{13}\).

=0

Ai h mk mk se h lai

1 - 1 = 0 

k cho mình nha

1-1=0

k mk nha

Ta có \(\frac{1}{2004}.\left(1-\frac{1}{2005}\right).\left(1-\frac{1}{2006}\right).\left(1-\frac{1}{2007}\right).\left(1-\frac{1}{2008}\right)\)

\(=\frac{1}{2004}.\frac{2004}{2005}.\frac{2005}{.2006}.\frac{2006}{2007}.\frac{2007}{2008}\)

\(=\frac{1.2004.2005.2006.2007}{2004.2005.2006.2007.2008}\)

\(=\frac{1}{2008}\)

\(\frac{1}{2004}\cdot\left(1-\frac{1}{2005}\right)\cdot\left(1-\frac{1}{2006}\right)\cdot\left(1-\frac{1}{2007}\right)\cdot\left(1-\frac{1}{2008}\right)\)

\(=\frac{1}{2004}\cdot\frac{2004}{2005}\cdot\frac{2005}{2006}\cdot\frac{2006}{2007}\cdot\frac{2007}{2008}\)

\(=\frac{1\cdot2004\cdot2005\cdot2006\cdot2007}{2004\cdot2005\cdot2006\cdot2007\cdot2008}=\frac{1}{2008}\)

Giấu chấm là gì vậy

1 - 1 = 0

tk nha cảm ownnnnnnnnnnnnnnnnn !!!! ^^

1 - 1 = 0

Nhớ k cho mình nha!

1+1+1-1+1+2+7+7+8+9+8+7+7+6+8+6+9+6+9+6+86+8=106+86

                                                                                 =192

nhớ k cho mình nha