What are the possible rational zeros of f(x) = 3x3 - 4x2 - 7x + 21 ?

Question

terenzreignz · Answer

The rational root test... This involves finding all possible factors of the constant, and all possible factors of the leading coefficient $\large(3x^3)$

terenzreignz · Answer

The constant is 21... what are the factors of 21?

jjenk · Answer

1, 3, 7,21

terenzreignz · Answer

That's good :)
Now what about the factors of 3, the leading coefficient?

jjenk · Answer

1 3

terenzreignz · Answer

Okay, great :)
Now, as per the "Rational Root Test"
the possible rational roots would be all possible numbers of the form
$$\Large \pm \frac{p}q$$
Where p is a factor of the constant (21) and q is a factor of the leading coefficient (3)

Just list them all out and exhaust the list :D

jjenk · Answer

$$\pm1\pm3\pm7\pm21$$

terenzreignz · Answer

What about $$\Large \pm \frac73$$?

jjenk · Answer

ok I understand now!! Thank You!!