If a+b = 8 and ab =15, then $$a^{3} + b^{3}$$ is
It is given that : $$(a+b)=8$$ and $$ab=15$$
Using the expression, $$(a^3+b^3)=(a+b)(a^2+b^2-ab)$$
= $$(8)(a^2+b^2-15)$$
Also, $$(a^2+b^2)=(a+b)^2-2ab$$
= $$8[((a+b)^2-2ab)-15]$$
= $$8[(8^2-(2 \times 15))-15]$$
= $$8(64-30-15) = 8 \times 19$$
= $$152$$
=> Ans - (C)
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