Robert Z. answered • 07/10/20
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Enthusiastic Explainer: Physics & Math
The tedious first step is to use the Rational Zeroes test to find an x value that yields a zero result. Applying the test, the following candidates are presented (all + or -): 4, 2, 4/3, 1, 2/3, 1/2, 1/3, 1/6
That's a total of 16 possible roots. Trial and error ensues; I got a hit trying 1/2; as it turns out, -2 and +2/3 also work.
The next step is to divide the cubic by x-a, where "a" is the value from Step 1 that worked. This produces a quadratic which can then be factored by previously learned techniques.
