Question

Find the cube root of each of the following numbers: [4 MARKS]

1. $8\times 64$

2. $(-216)\times 1728$

3. $27\times (-2744)$

4. $(-125)\times (-3375)$

Answer 1

Application: 1 Mark each

$\left(1\right)8\times 64=2\times 2\times 2\times 2\times 2\times 2\times 2\times 2\times 2$

$\sqrt[3]{38\times 64}=2\times 2\times 2=8$


$\left(2\right)216\times 1728=2\times 2\times 2\times 3\times 3\times 3\times 2\times 2\times 2\times 2\times 2\times 2\times 3\times 3\times 3$

$\sqrt[3]{3(-216)\times 1728}=-(2\times 3\times 2\times 2\times 3)=-72$


$\left(3\right)27\times 2744=3\times 3\times 3\times 2\times 2\times 2\times 7\times 7\times 7$

$\sqrt[3]{327\times (-2744)}=-(3\times 2\times 7)=-42$


$\left(4\right)125\times 3375=5\times 5\times 5\times 3\times 3\times 3\times 5\times 5\times 5$

$\sqrt[3]{3(-125)\times (-3375)}=5\times 3\times 5=75$