If (a + b) = 6 and ab = 8, then $$(a^3 + b^3)$$ is equal to:
Given that,
$$a+b=6 $$ and $$ ab=8$$
We know that,
$$(a+b)^3=a^3+b^3+3ab(a+b)$$
$$\Rightarrow (6)^3=a^3+b^3+3\times8\times(6)$$
$$\Rightarrow 216=a^3+b^3+144$$
$$\Rightarrow a^3+b^3=216-144=72$$
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