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Without actually calculating the cubes, evaluate the expression `(30)^(3)+(-18)^(3)+(-12)^(3)`.

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To evaluate the expression \(30^3 + (-18)^3 + (-12)^3\) without actually calculating the cubes, we can use the identity for the sum of cubes. ### Step-by-Step Solution: 1. **Identify the values of a, b, and c**: Let \(a = 30\), \(b = -18\), and \(c = -12\). 2. **Check if \(a + b + c = 0\)**: \[ a + b + c = 30 + (-18) + (-12) = 30 - 18 - 12 = 0 \] Since \(a + b + c = 0\), we can use the special case of the identity. 3. **Use the identity**: The identity states that if \(a + b + c = 0\), then: \[ a^3 + b^3 + c^3 = 3abc \] 4. **Calculate \(abc\)**: \[ abc = 30 \times (-18) \times (-12) \] First, calculate \(30 \times (-18)\): \[ 30 \times (-18) = -540 \] Now, multiply by \(-12\): \[ -540 \times (-12) = 6480 \] 5. **Substitute back into the identity**: Now, substituting \(abc\) back into the identity: \[ a^3 + b^3 + c^3 = 3 \times 6480 = 19440 \] ### Final Result: Thus, the value of \(30^3 + (-18)^3 + (-12)^3\) is \(19440\). ---
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