Wykonajmy obliczenia.

a)

$3\cdot \left(-21\right)=-63$

$\left(-4\right)\cdot 12=-48$

$\left(-18\right)\cdot \left(-3\right)=54$

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b)

$35:\left(-7\right)=-5$

$\left(-84\right):2=-42$

$\left(-90\right):\left(-30\right)=3$

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c)

$\left(-2\right)\cdot 3\cdot \left(-9\right)=-6\cdot \left(-9\right)=54$

$\left(-6\right)\cdot \left(-8\right)\cdot \left(-2\right)=48\cdot \left(-2\right)=-96$

$20:\left(-5\right):\left(-2\right)=-4:\left(-2\right)=2$

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d)

${\left(-8\right)}^2=\left(-8\right)\cdot \left(-8\right)=64$

${\left(-2\right)}^3=\left(-2\right)\cdot \left(-2\right)\cdot \left(-2\right)=4\cdot \left(-2\right)=-8$

${\left(-1\right)}^3=\left(-1\right)\cdot \left(-1\right)\cdot \left(-1\right)=1\cdot \left(-1\right)=-1$