If F (x) =3x^2 +5x -2 Find F(-2) F(4), Can You Help?

If you have a statement,

F(x) = 3X^2 + 5X - 2 it is telling you that this is the function for all values of X

so when you are asked to find F(-2) or F(4), you are being asked to substitute the values for X in the function.

So F(-2) = 3(-2)^2 + 5(-2) - 2 ..... You then solve for the answer

Repeat the process for F(4)

The answers you were given by 'Chuckfoor' are correct, I just thought you may want the process on how he got it.

F(x) = 3x² + 5x - 2 = (3x - 1)(x + 2)

F(-2) = (3(-2) - 1)((-2)+2) = (-6-1)(0) = 0
F(4) = (3(4) - 1)((4) + 2) = (12-1)(6) = 11*6 = 66

A reasonable way to compute this using computer code or a calculator is this.
F(x) = (3x + 5)x - 2
At each step, you perform a multiplication (by x) and an addition (by a constant).

F(-2) = (3(-2)+5)(-2) - 2 = (-6+5)(-2) - 2 = -1*-2 - 2 = 2 - 2 = 0
F(4) = (3(4)+5)(4) - 2 = (12+5)(4) - 2 = 17*4 - 2 = 68 - 2 = 66

H(-1)= (2(-1) + 1)³