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) = 2x3-9x2+x+12, g(x) = 3-2x
We have,
f(x) = 2x3-9x2+x+12 and g(x) = 3-2x
In order to find g (x) = 3 – 2x = 2 (x - ) is a factor of f (x) or not, it is sufficient to prove that f (
) = 0
Now,
f(x) = 2x3-9x2+x+12
f () = 2 (
)3 – 9 (
)2 +
+ 12
= -
+
+ 12
=
= 0
Hence, g (x) is a factor of f (x).