If f(2)=0 then calcuate the value of the following functions....

[scibecco]

Hi all,
I was working through my homework questions and came across a problem I don't recall being taught how to answer.
It is the following:

If f(2)=0, g(2)=8, and h(2)=-1, then calculate the value of the following functions at x=2

a) (3f+4g) (2)

b) f+g/gh (2)

I really appreciate any help,
Thanks!!

 

[Deleted member 4993]

Hi all,
I was working through my homework questions and came across a problem I don't recall being taught how to answer.
It is the following:

If f(2)=0, g(2)=8, and h(2)=-1, then calculate the value of the following functions at x=2

a) (3f+4g) (2)

b) f+g/gh (2)

I really appreciate any help,
Thanks!!

What are your thoughts?

Please share your work with us ...even if you know it is wrong.

If you are stuck at the beginning tell us and we'll start with the definitions.

You need to read the rules of this forum. Please read the post titled "Read before Posting" at the following URL:

http://www.freemathhelp.com/forum/announcement.php?f=33

 

[scibecco]

What are your thoughts?

Please share your work with us ...even if you know it is wrong.

If you are stuck at the beginning tell us and we'll start with the definitions.

You need to read the rules of this forum. Please read the post titled "Read before Posting" at the following URL:

http://www.freemathhelp.com/forum/announcement.php?f=33

I’m only used to questions such as “If f(x)=2x+1, then find f(2) (simple substitution). That’s why this question tripped me up a lot. I’ve thought a lot about it but can’t seem to crack it.
Here is an example of my working for question a)
a) (3f+4g) (2)

3x2x0 (because f(2)=0 + 4x2x8 (because f(g)=8 x 2
I know this is wrong but the trouble is I just can’t figure out any way it would work out!
Thanks once again!

 

[mmm4444bot]

Here is an example of my working for question a)
a) (3f+4g) (2)

3x2x0 (because f(2)=0 + 4x2x8 (because f(g)=8 x 2

I think your issue may be the function notation.

(3f + 4g)(x) is function notation for the following combination of functions f and g:

3*f(x) + 4*g(x)

Therefore, the notation (3f + 4g)(2) means 3*f(2) + 4*g(2).

The asterisks are multiplication signs. :cool:

 

[scibecco]

I think your issue may be the function notation.

(3f + 4g)(x) is function notation for the following combination of functions f and g:

3*f(x) + 4*g(x)

Therefore, the notation (3f + 4g)(2) means 3*f(2) + 4*g(2).

The asterisks are multiplication signs. :cool:

Thanks for your reply!
Ah, something so simple and it was right in front of my eyes!
So does this simply translate to 3*0 + 4*8(2)?

 

[ksdhart2]

Thanks for your reply!
Ah, something so simple and it was right in front of my eyes!
So does this simply translate to 3*0 + 4*8(2)?

Almost, but not quite. You've correctly plugged in f(2), but incorrectly plugged in g(2). You're given that g(2) = 8, not 8(2) which would be interpreted as multiplication (i.e. 8 * 2 = 16).