Consider this expression:
[tex]\[ \frac{3x}{x+2} + \frac{4x}{x-2} \][/tex]

Find the values for [tex]\( a, b \)[/tex], and [tex]\( c \)[/tex] that make this expression equivalent to:
[tex]\[ \frac{ax^2 + bx}{x^2 + c} \][/tex]

[tex]\[ a = \square \][/tex]
[tex]\[ b = \square \][/tex]
[tex]\[ c = \square \][/tex]



Answer :

To solve for the values of [tex]\(a\)[/tex], [tex]\(b\)[/tex], and [tex]\(c\)[/tex] that make the given expression [tex]\(\frac{3x}{x+2} + \frac{4x}{x-2}\)[/tex] equivalent to [tex]\(\frac{ax^2 + bx}{x^2 + c}\)[/tex], we will perform the following steps:

1. Find a common denominator for the two fractions.
2. Combine the fractions and simplify the numerator.
3. Identify the coefficients that correspond to [tex]\(a\)[/tex], [tex]\(b\)[/tex], and [tex]\(c\)[/tex].

### Step 1: Find a common denominator
The fractions are:
[tex]\[ \frac{3x}{x+2} \quad \text{and} \quad \frac{4x}{x-2} \][/tex]

The common denominator will be [tex]\((x+2)(x-2)\)[/tex].

### Step 2: Combine the fractions and simplify
First, rewrite each fraction with the common denominator:
[tex]\[ \frac{3x}{x+2} = \frac{3x(x-2)}{(x+2)(x-2)} \quad \text{and} \quad \frac{4x}{x-2} = \frac{4x(x+2)}{(x+2)(x-2)} \][/tex]

Now combine the fractions:
[tex]\[ \frac{3x(x-2) + 4x(x+2)}{(x+2)(x-2)} \][/tex]

Expand the numerators:
[tex]\[ 3x(x-2) = 3x^2 - 6x \quad \text{and} \quad 4x(x+2) = 4x^2 + 8x \][/tex]

Add these together:
[tex]\[ 3x^2 - 6x + 4x^2 + 8x = 7x^2 + 2x \][/tex]

So, the combined fraction is:
[tex]\[ \frac{7x^2 + 2x}{x^2 - 4} \][/tex]

### Step 3: Identify the coefficients
We need the expression [tex]\(\frac{ax^2 + bx}{x^2 + c}\)[/tex] to match the form of [tex]\(\frac{7x^2 + 2x}{x^2 -4}\)[/tex].

By comparing:
[tex]\[ ax^2 + bx \quad \text{with} \quad 7x^2 + 2x \][/tex]

And:
[tex]\[ x^2 + c \quad \text{with} \quad x^2 - 4 \][/tex]

We find:
[tex]\[ a = 7, \quad b = 2, \quad \text{and} \quad c = -4 \][/tex]

### Final Answer
So, the values are:
[tex]\[ a = 7, \quad b = 2, \quad c = -4 \][/tex]