If a + b = 4 and ab = -5, then what is the value of $$a^{3} + b^{3}$$?
Given :  $$ab=-5$$ -----------(i)
Also, $$a+b=4$$ -----------(ii)
Cubing both sides, we get :
=> $$(a+b)^3=(4)^3$$
=> $$a^3+b^3+3ab(a+b)=64$$
Substituting values from equation (i) and (ii)
=> $$a^3+b^3+3(-5)(4)=64$$
=> $$a^3+b^3=64+60=124$$
=> Ans - (C)
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