a, 369 - (|-206| - 15 ) - ( - 206 + | -369|)
369-(206 - 15 ) + 206 - 369
= 369 - 206 + 15 + 206 - 369
= ( 369 - 369 ) + ( -206 + 206 ) + 15
= 0 + 0 + 15
= 15
b, 345 - 150 : [ ( \(3^3\)- 24 )\(^2\)- ( -21 ) ] + 2016\(^0\)
= 345 - 150 : [(27 - 24)\(^2\) + 21] + 1
= 345 - 150 : [3\(^2\)+ 21 ] + 1
= 345 - 150 : 30 + 1
= 345 - 5 + 1
= 341
c, - 2 + 6 - 12 + 16 -....-92 + 96
ta có : ( 6 + 16 + ... + 96 ) + ( -2 + -12 + ... + -92 )
mỗi bên đều có 10 số hạng
=> [ ( 6 + 96 ) . 10 : 2 ] + [ ( -2 + -92 ) . 10 : 2 ]
=> 510 + -470
= 40
\(a,369-\left(\left|-206\right|-15\right)-\left(-206+\left|-369\right|\right)\)
\(=369-\left(206-15\right)+206-369\)
\(=369-206+15+206-369\)
\(=\left(369-369\right)+\left(-206+206\right)+15\)
\(=0+0+15=15\)
\(b,345-150:\left[\left(3^3-24\right)^2-\left(-21\right)\right]+2016^0\)
\(=345-150:\left[\left(27-24\right)^2+21\right]+1\)
\(=345-150:\left[3^2+21\right]+1\)
\(=345-150:30+1\)
\(=345-5+1=341\)
\(c,-2+16-12+...+96\)
Ta có: \(\left[-2+...+\left(-92\right)\right]+\left[6+16+...+96\right]\)
Hai bên có \(10\) số hạng.
\(\Rightarrow\left\{\left[-2+\left(-12\right)\right].10:2\right\}+\left\{\left[6+16\right].10:2\right\}\)
\(\Rightarrow510+\left(-470\right)=40\)
