f ( x ) + g ( x ) = x 3 + 2 x 2 + 3 x 2 − 1 = x 3 + 5 x 2 − 1 D : x ∈ R
f ( x ) − g ( x ) = x 3 + 2 x 2 − ( 3 x 2 − 1 ) = x 3 + 2 x 2 − 3 x 2 + 1 = x 3 − x 2 + 1 D : x ∈ R
f ( x ) \cdotg ( x ) = ( x 3 + 2 x 2 ) ( 3 x 2 − 1 ) = 3 x 5 − x 3 + 6 x 4 − 2 x 2 = 3 x 5 + 6 x 4 − x 3 − 2 x 2 D : x ∈ R
g ( x ) f ( x ) = 3 x 2 − 1 x 3 + 2 x 2 3 x 2 − 1 = 0 3 x 2 = 1 x 2 = 3 1 x = − 3 3 ∧ x = 3 3 D : x ∈ ( − ∞ , − 3 3 ) ∪ ( 3 3 , ∞ )
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We found the following for the functions: f + g = x 3 + 5 x 2 − 1 , f − g = x 3 − x 2 + 1 , f ⋅ g = 3 x 5 + 6 x 4 − x 3 − 2 x 2 , and g f = 3 x 2 − 1 x 3 + 2 x 2 with respective domains. The domains for addition, subtraction, and multiplication are all real numbers, while the domain for division excludes values where the denominator is zero. Overall, handling polynomial operations requires considering the domain restrictions primarily in division cases.
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