Question

f(3)=|x+1|

Answer 1

replace x with 3 then evaluate. I would like for you to try it.

Answer 2

i thought f(3) = y hense the problem so it could either be 2 or 4

Answer 3

f(3) = | x + 1 |
f(3) = | 3+1 |
f(3) = | 4 |
or f(3) = 4

Answer 4

the notation is what takes time getting used to.

Answer 5

yeah, i just keep thinking because of placement f is actually = y

Answer 6

f(x) is a function. its like a machine. You put things into it, and it returns something. When you see something like:
\[f(x) = 2x\]we are specifically telling you what the function does. For every input 'x', it multiplies it by 2, and gives it back.

So what would f(3) be in this case? it would be:
\[f(3) = 2(3) = 6\] so f(3) = 6. Input was 3, output was 6.

Whats f(8)? \[f(8) = 2(8) = 16\] f(8) = 16. Input was 8, output was 16.

Answer 7

oh so before this you were using 'y =' instead of 'f(x) =' ?

Answer 8

so if f(10)=7x+9 function = 70 x 10 +9 or 79?

Answer 9

that is correct. if the function was:
\[f(x) = 7x+9\]then:\[f(10) = 7(10)+9 = 70+9 = 79\]:)

Answer 10

joe keep it up u r a gr8 mathematician

Answer 11

I hope i never have to ask this again, so sorry for any confusion, very frustrating for me

Answer 12

it just takes practice, and learning the terminology. Thats probably the most confusing part.

Answer 13

I wonder what's so confusing about "replace x with 3, then evaluate".

Answer 14

I try to make it seem simpler. What's wrong with that approach?

Answer 15

of course its not confusing to us <.< ive taught at a high school for 2 years. People find this very very confusing.

Answer 16

Okay how about this...