Question

If f(x) = x^2 - 4x + 2, then f(a - b) = ?

Answer 1

One way of doing this:

Write out the function: f(x) = x^2 - 4x + 2

Wherever you see (x) or x, replace it with (b-a).

Thus, f(x) becomes f(b-a).

Evaluate the right side.

Hint: x^2 becomes (b-a)^2.

MUST use parentheses.

Answer 2

DUH, I'm should've known that. Brain lapse. Thanks. The a's and b's confused me since I didn't see any 'x'.

Answer 3

Very simple
Replace every x with a-b
f(a-b)=(a-b)^2-4(a-b)+2

and you can simplify it if you wish

Answer 4

Typo: I meant a-b, not b-a.

Answer 5

3mar managed to catch that before I did. Bully for him.