\(\text{14-(-15)-21}\)
\(=14+15-21\)
\(=29-21\)
\(=8\)
\(321+\left\{-15+\left[30+\left(-321\right)\right]\right\}\)
\(=321+\left(-15\right)+30+\left(-321\right)\)
\(=\left(321+\left(-321\right)\right)+\left(\left(-15\right)+30\right)\)
\(=0+15\)
\(=15\)
\(\text{(2016+432)+[168+(-2016)]}\)
\(=2016+432+168+\left(-2016\right)\)
\(=\left[2016+\left(-2016\right)\right]+\left(432+168\right)\)
\(=0+600\)
\(=600\)
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