Answer:
a = 0
b = 2
Step-by-step explanation:
Synthetic division gives rise to two equations:
b -2a = 2
b +2a = 2
The solution to these equations is (a, b) = (0, 2).
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The remainder from the division is the lower-right sum shown in the attached tables. For the factor x+2, the remainder from dividing your cubic by x+2 is (4b-8a-8). Setting this to zero and putting it into standard form gives the first equation shown above.
The remainder from division by (x-2) is (4b+8a-4). Setting this to 4 and putting the result into standard form gives the second equation above.
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Pen skips and chocolate smudges make the first attachment less "professional" than it might otherwise be. Please forgive. The graph in the second attachment verifies this result.
