Evaluate: {(28)3 + (-15)3 + (-13)3}.

We have,

[(28)3 + (-15)3 + (-13)3]


Now putting a = 28, b = - 15 and c = - 13


Now, a + b + c = 28 – 15 – 13


= 28 – 28


= 0


So, x3 + y3 + z3 = 3xyz


(28)3 + (-15)3 + (-13)3 = 3 × (28) × (-15) × (-13)


= 84 × 195


= 16380


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