# Basic Algebra Simplifying a complex fraction

1. Dec 24, 2011

### Femme_physics

Last edited by a moderator: May 5, 2017
2. Dec 24, 2011

### JHamm

Just to clarify
$$C = \frac{62.5}{(x+3)(x+4)}$$
and
$$R = 1 + \frac{0.625}{(x+3)(x+4)} + \frac{7}{(x+3)}$$

?

3. Dec 24, 2011

### Femme_physics

I don't know, I only know what I'm trying to solve not other suppositions

4. Dec 24, 2011

### HallsofIvy

Then I guess the question is: what are you trying to do?

5. Dec 24, 2011

### micromass

In the last line, I don't really see why you don't simplify by eliminating (x+3)(x+4).

6. Dec 24, 2011

### I like Serena

How does the smiley factor in?

Btw, it looks right, but it would be nice if you wrote things down a bit neater.
And you can simplify it further as micro suggested.

7. Dec 24, 2011

### Femme_physics

Well, I just have a engineering transfer (C/R) function that I'm looking to simplify. as per title .

The question is "am I right so far?" , basically. Just checking I didn't do a math error.

True! I did, and went on to simplify ....
http://img39.imageshack.us/img39/1011/cr2b.jpg [Broken]

Can I simplifiy it even more?

Smilies are an intensively complex algorithmic field of math. I don't even wanna get into it. Plus, somehow all my results to that end up in a frowny face :(

You can consider this smiley as a stray. Deviating from another exercise. Sneaky little bastard..

Last edited by a moderator: May 5, 2017
8. Dec 24, 2011

### technician

Can't you just multiply out the brackets under the division line to get
X^2 + 14x + 40.625 as the denominator

9. Dec 24, 2011

### Femme_physics

Thing is I'm not sure if I'll consider having a power of 2 in my equation all that simplified?

10. Dec 24, 2011

### I like Serena

11. Dec 24, 2011

### Femme_physics

rofl!

12. Dec 24, 2011

### SammyS

Staff Emeritus
I hate to butt in, because I know that you and I like Serena have developed a rapport .

What is the expression you are starting with?

Is it :
$\displaystyle\frac{C}{R}=\frac{\displaystyle\frac{62.5}{(x+3)(x+4)}}{\displaystyle 1 + \frac{0.625}{(x+3)(x+4)} + \frac{7}{(x+3)}}\ \ ?$​

Last edited by a moderator: May 5, 2017
13. Dec 24, 2011

### Femme_physics

Last edited by a moderator: May 5, 2017
14. Dec 24, 2011

### SammyS

Staff Emeritus
That result looks right, with or without the smiley.

15. Dec 24, 2011

Thanks!