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Simplify (4a+2b)^(3)+(4a-2b)^(3)....

Simplify `(4a+2b)^(3)+(4a-2b)^(3)`.

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To simplify the expression \((4a + 2b)^3 + (4a - 2b)^3\), we can use the formulas for the sum of cubes and the difference of cubes. ### Step-by-Step Solution: 1. **Identify the Terms**: Let \( A = 4a \) and \( B = 2b \). Thus, we can rewrite the expression as: \[ (A + B)^3 + (A - B)^3 \] 2. **Use the Formulas**: We will use the formulas: \[ (A + B)^3 = A^3 + B^3 + 3AB(A + B) \] \[ (A - B)^3 = A^3 - B^3 - 3AB(A - B) \] 3. **Calculate Each Part**: - For \((A + B)^3\): \[ (4a + 2b)^3 = (4a)^3 + (2b)^3 + 3(4a)(2b)(4a + 2b) \] \[ = 64a^3 + 8b^3 + 3 \cdot 8ab(4a + 2b) \] \[ = 64a^3 + 8b^3 + 24ab(4a + 2b) \] - For \((A - B)^3\): \[ (4a - 2b)^3 = (4a)^3 - (2b)^3 - 3(4a)(2b)(4a - 2b) \] \[ = 64a^3 - 8b^3 - 3 \cdot 8ab(4a - 2b) \] \[ = 64a^3 - 8b^3 - 24ab(4a - 2b) \] 4. **Combine the Results**: Now, we add the two results: \[ (4a + 2b)^3 + (4a - 2b)^3 = (64a^3 + 8b^3 + 24ab(4a + 2b)) + (64a^3 - 8b^3 - 24ab(4a - 2b)) \] 5. **Simplify**: - The \(64a^3\) terms add up: \[ 64a^3 + 64a^3 = 128a^3 \] - The \(8b^3\) and \(-8b^3\) cancel out: \[ 8b^3 - 8b^3 = 0 \] - The \(24ab(4a + 2b)\) and \(-24ab(4a - 2b)\) combine: \[ 24ab(4a + 2b) - 24ab(4a - 2b) = 24ab(4a + 2b - 4a + 2b) = 24ab(4b) \] \[ = 96ab^2 \] 6. **Final Result**: Combining all parts, we have: \[ 128a^3 + 96ab^2 \] ### Final Answer: \[ 128a^3 + 96ab^2 \]
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