Problem 8 of 7
Use Pascal's Triangle to expand (3a-b)^3.
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select coefficient row and apply powers.
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Use Pascal row n and apply signs from the binomial terms.
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Solution
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1. Select Pascal's Triangle row matching the exponent.
2. Assign descending powers of the first term and ascending powers of the second.
3. Apply signs and simplify coefficients.
Use the worked steps, then substitute the final answer back into the original relationship to confirm it satisfies the prompt.
Using row n-1 for power n.