# Math Help - f(x) function equations

1. ## f(x) function equations

Hi! I'm pretty sure I know how to do the basics of these equations, but this one really tripped me up. Can anyone show me how to do it?

f(x) = 2x³ - x² - 4x + 5

I need to find $f(-x)$.

Any help would be really appreciated!

2. wherever you see an x, replace it with a -x, simplify and you are done

3. I know I have to replace it. but I can't seem to simplify it and none of it looks right

I got f(x) = -2x³ + x² + 4x + 5

is that right? and if it isn't, can you perhaps explain it a little further?

thanks!

4. $f(x) = 2x^3-x^2-4x+5$

$f(-x) = 2(-x)^3-(-x)^2-4(-x)+5$

$f(-x) = -2x^3-x^2+4x+5$