The function
f is defined by f(x)=2x^2 -1
.
Find
f(4x).
I'm really having trouble understanding what this question wants. I got 32x^2 -1 but I don't think i did it right.

Question

The function 
f is defined by f(x)=2x^2 -1
 .
Find 
f(4x).
I'm really having trouble understanding what this question wants. I got 32x^2 -1 but I don't think i did it right.

alyssa_xo · Answer

replace x with (4x)
$f(4x)=2(4x)^2-1=2*16x^2-1=32x^2-1$

you did it right

anonymous · Answer

okay. Thank you. I just wasn't sure if i replace it with 4 or 4x. Thank you! If I need more help can I tag you?

alyssa_xo · Answer

sure

anonymous · Answer

Thank you. Every time I post questions no one helps, this site has failed me so many times.

anonymous · Answer

I'll close the question now.

alyssa_xo · Answer

it depends on a lot of stuff, name time of day, and what day it is.
on weekends/fridays nobody's really on

alyssa_xo · Answer

alright

alyssa_xo · Answer

namely*