Evaluating Functions Homework Help

[ninjamonke]

Homework Statement

[PLAIN]http://img89.imageshack.us/img89/6410/c3602011091514253311.jpg

Homework Equations

Both a and b.

The Attempt at a Solution

For problem a, I don't know what to after that. If you could direct/tell me what to do next, I'd be able to figure it out.
For problem b, I don't know how to set it up.

 

[A_B]

For a. , try getting rid of some denominators, it comes out very nicely.
For b. Do exactly what you did for a. Only now because you have the function F() in the expression multiple times, so you'll have to do the substitution multiple times.

Hope this helps enough.. but not too much.

 

[ninjamonke]

For a, do I multiply everything on the bottom by y?

 

[HallsofIvy]

Yes, multiply both numerator and denominator by y.

 

[ninjamonke]

This is my answer that I got.

[PLAIN]http://img838.imageshack.us/img838/1974/c36020110915181646.jpg

Is it right?

Yes, multiply both numerator and denominator by y.

I did that but I don't know if I did it correctly.

[PLAIN]http://img269.imageshack.us/img269/8973/c360201109151748431.jpg

 

[J2R]

I re-wrote the denominator like this:

3y+4/y - 3/1

From here I just cross multiplied:

3y + 4 - 3y

Combine like terms and you end up with 4/4.

F(3y+4/y) = 1

 

[A_B]

Your answer to a. is correct ninjamonke, now for b. !