In each of the following, use factor theorem to find whether polynomial g(x) is a factor of polynomial f(x) or, not:

f(x) = 3x3+x2-20x+12, g(x) = 3x-2

We have,

f(x) = 3x3+x2-20x+12 and g(x) = 3x-2


In order to find whether g (x) is = 3x – 2 is a factor of f (x) or not, it is sufficient to show that f () = 0


Now,


f(x) = 3x3+x2-20x+12


f () = 3 ()3 + ()2 – 20 () + 12


= - + 12


=


= 0


Hence, g (x) is a factor of f (x).


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