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Without actually calculating the cubes, find the value of 483 – 303 – 183. |
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Answer» We know that x3 + y3 + z3 – 3xyz = (x + y + z) (x2 + y2 + z2 – xy – yz – zx). If x + y + z = 0, then x3 + y3 + z3 – 3xyz = 0 or x3 + y3 + z3 = 3xyz. We have to find the value of 483 – 303 – 183 = 483 + (–30)3 + (–18)3 . Here, 48 + (–30) + (–18) = 0 So, 483 + (–30)3 + (–18)3 = 3 × 48 × (–30) × (–18) = 77760 |
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