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If $$a^{3} + b^{3}$$ = 19 and ab = -6 , then what is the value of a + b?
$$a^{3}+b^{3}=(a+b)^{3}-3ab(a+b)$$
$$19=(X)^{3}-3(-6)(X)$$
$$X^{3}+18X-19=0$$
by option verification, only X = 1 satisfies the above equation.
so the answer is option C.
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