Subtract like terms: Subtract the like terms.Subtract the coefficients of the like terms, which are the terms with the same power of a.For a3 terms: 6a3−5a3=1a3 or simply a3.For a2 terms: 7a2−9a2=−2a2.For a terms: There is no 'a' term in the first expression, so we just have −a from the second expression.
Combine results: Combine the results from Step 1.Combine the simplified terms to get the final expression.a3−2a2−a.
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