=2013.7645+(2013+1).2355-1355

=2013.7645+2013.2355+2355-1355

=2013.(7645+2355)+1000

=2013.10000+1000

=20130000+1000

=20131000

a, S
b, Đ

Bài 5 : 

Đánh dấu vào câu b 

Bài 6 : 

\(468\times135=63180\)

\(579\times254=147066\)

\(936\times205=191880\)

b c a b d

b,c,a,b,d nha bn

học tốt

chụp ngiêng thế

tra Google 

\(B=|2014-2x|+|2016-2x|\)

\(=|2014-2x|+|2x-2016|\ge|2014-2x+2x-2016|\)

Hay \(B\ge2\)

Dấu"="xảy ra \(\Leftrightarrow\left(2014-2x\right)\left(2x-2016\right)\ge0\)

\(\Leftrightarrow\hept{\begin{cases}2014-2x\ge0\\2x-2016\ge0\end{cases}}\)hoặc \(\hept{\begin{cases}2014-2x< 0\\2x-2016< 0\end{cases}}\)

\(\Leftrightarrow\hept{\begin{cases}2x\le2014\\2x\ge2016\end{cases}\left(loai\right)}\)hoặc\(\hept{\begin{cases}2x>2014\\2x< 2016\end{cases}}\) 

\(\Leftrightarrow\hept{\begin{cases}x>1007\\x< 1008\end{cases}}\)

\(\Leftrightarrow1007< x< 1008\)

Vậy \(B_{min}=2\)\(\Leftrightarrow1007< x< 1008\)

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