MHB Simplifying by combining terms

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    Simplifying Terms
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The discussion focuses on simplifying the expression $$\frac{1}{y+1}+\frac{2}{x+2}+\frac{\frac{x+2}{y+1}-2}{x+2}$$ by addressing the third term, which is a compound fraction. Participants clarify that to simplify, one should multiply the numerator and denominator by $(y + 1)$ to eliminate the fraction. The simplification leads to the expression $$\frac{x - 2y}{(x+2)(y + 1)}$$, and further steps involve combining fractions correctly. The conversation highlights the importance of careful manipulation of terms to achieve the final simplified form.
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Ok.. What about this one?

$$\frac{1}{y+1}+\frac{2}{x+2}+\frac{\frac{x+2}{y+1}-2}{x+2}$$

this is where I am at:

\left(\frac{x+2}{y+1}-2\right)
 
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headbang said:
Ok.. What about this one?

$$\frac{1}{y+1}+\frac{2}{x+2}+\frac{\frac{x+2}{y+1}-2}{x+2}$$

this is where I am at:
Let's clear that mess in the 3rd term:
$$\frac{1}{y+1}+\frac{2}{x+2}+\frac{\frac{x+2}{y+1}-2}{x+2} \cdot \frac{(y + 1)}{(y + 1)}$$

$$\frac{1}{y+1}+\frac{2}{x+2}+\frac{(x+2) - 2(y + 1)}{(x+2)(y + 1)}$$

$$\frac{1}{y+1}+\frac{2}{x+2}+\frac{x - 2y}{(x+2)(y + 1)}$$
Now just add the fractions. Give it a try and tell us how it goes from here.

-Dan
 
Can the ansver be:

$$\frac{2+x}{4y}$$ And i stil don't understand how you solved the messy 3rd term..?

what i did from where you left me..

$$\frac{x+2+2y+2+x-y}{(x+2)(y+1)}$$

$$\frac{4+2x+y}{(8x+2)(y+1)}$$

$$\frac{2*2+x*x+y}{x*y+2y+y+y+2}$$
 
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headbang said:
Ok.. What about this one?

$$\frac{1}{y+1}+\frac{2}{x+2}+\frac{\frac{x+2}{y+1}-2}{x+2}$$

this is where I am at:

\left(\frac{x+2}{y+1}-2\right)

I moved the posts associated with your new problem into a separate thread. We ask that new questions not be tagged onto an existing thread...this way the original thread does not potentially become convoluted and hard to follow. :D
 
headbang said:
Can the ansver be:

$$\frac{2+x}{4y}$$ And i stil don't understand how you solved the messy 3rd term..?

what i did from where you left me..

$$\frac{x+2+2y+2+x-y}{(x+2)(y+1)}$$
First things first: The equation above is almost correct. You missed a 2 in the last term in the numerator. It should be
$$\frac{x+2+2y+2+x-2y}{(x+2)(y+1)}$$

Okay, the third term in your problem is what is known as a "compound fraction." Compound fractions have fractions in the numerator, denominator, or both. Let's take this one step by step.
[math]\frac{\frac{x + 2}{y + 1} - 2}{x + 2}[/math]

The goal here is to remove the fraction in the numerator. Clearly if we multiply the numerator by y + 1 the fraction goes away. And what we do to the numerator we need to do to the denominator. So:
[math]\frac{\frac{x + 2}{y + 1} - 2}{x + 2} \cdot \frac{y + 1}{y + 1}[/math]

Now simplify:
[math]\frac{\frac{x + 2}{y + 1} - 2}{x + 2} \cdot \frac{y + 1}{y + 1} = \frac{\left ( \frac{x + 2}{y + 1} \right ) (y + 1) - 2(y + 1)}{(x + 2)(y + 1)}[/math]

[math]\frac{(x + 2) - 2(y +1)} {(x + 2)(y + 1)}[/math]

And now go from there.

-Dan
 
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$$\frac{x+2+2y+2+x-2(y+1)}{(x+2)(y+1)}$$

$$2y+2+x-2=x+2y$$

Ok?
 
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