( - 2013 ) + 21 + 19 + l - 2013 l
= ( - 2013 ) + 21 + 19 + 2013
= [ ( - 2013 ) + 2013 ] + ( 21 + 19 )
= 0 + 40
= 40
\(\left(-2013\right)+21+19+\left|-2013\right|\)
\(=\left[\left(-2013\right)+\left|-2013\right|\right]+\left(21+19\right)\)
\(=\left[\left(-2013\right)+2013\right]+\left(21+19\right)\)
\(=0+40\)
\(=40\)
chúc bạn học giỏi!
(-2013)+21+19+/-2013/
=(2013)+21+19+2013
=(-2013)+2013+(21+19)
=0+21+19
=40