Could you help me subtact this polynomials? (-8a^2+4a+2)-(8a+2)=
Expand (remove parentheses) and collect terms in decreasing powers of a:
(-8a^2+4a+2) = -8a^2+4a+2
-(8a+2) = -8a-2
Since the subtraction is implied in the negation of the secnd expression, you only have to add the two resulting expressions and regroup in decreasing powers of a.
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