<s>[INST] $ax^3+8x^2+bx+6$ is exactly divisible by $x^2-2x-3$, find the values of $a$ and $b$ Find the values of $a$ and $b$ for which the polynomial $ax^3+8x^2+bx+6$ is divisible by $x^2-2x-3$.
 [/INST] What are the roots of $x^2-2x-3$? They should also be roots in the 3rd degree polynomial.
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