1. The problem is to express the equation $$(2x + 1)(x - 3) = \frac{\square}{2x + 1} - \frac{\square}{x - 3}$$ by finding the numerators in the fractions on the right side.
2. Start by expanding the left side:
$$ (2x + 1)(x - 3) = 2x \cdot x + 2x \cdot (-3) + 1 \cdot x + 1 \cdot (-3) = 2x^2 - 6x + x - 3 = 2x^2 - 5x - 3 $$
3. To write the right side as a single fraction, find a common denominator:
$$ \frac{A}{2x + 1} - \frac{B}{x - 3} = \frac{A(x - 3) - B(2x + 1)}{(2x + 1)(x - 3)} $$
4. Since the left side equals the right side, their numerators must be equal:
$$ 2x^2 - 5x - 3 = A(x - 3) - B(2x + 1) $$
5. Expand the right side:
$$ A x - 3A - 2Bx - B = (A - 2B)x - (3A + B) $$
6. Equate coefficients of like terms:
- For $x^2$: Left side has $2x^2$, right side has none, so this suggests the right side must be adjusted to include $x^2$ terms. This means the initial assumption that the right side is a difference of two fractions with numerators $A$ and $B$ constants is incorrect.
7. Instead, let the numerators be linear expressions:
$$ \frac{Ax + C}{2x + 1} - \frac{Bx + D}{x - 3} $$
8. Then the combined numerator is:
$$ (Ax + C)(x - 3) - (Bx + D)(2x + 1) $$
9. Expand:
$$ A x^2 - 3 A x + C x - 3 C - 2 B x^2 - B x - 2 D x - D $$
10. Group like terms:
$$ (A - 2B) x^2 + (-3A + C - B - 2D) x + (-3C - D) $$
11. Set equal to left side numerator:
$$ 2 x^2 - 5 x - 3 $$
12. Equate coefficients:
$$ A - 2B = 2 $$
$$ -3A + C - B - 2D = -5 $$
$$ -3C - D = -3 $$
13. Solve the system:
From the third equation:
$$ -3C - D = -3 \implies D = -3C + 3 $$
Substitute $D$ into the second equation:
$$ -3A + C - B - 2(-3C + 3) = -5 $$
$$ -3A + C - B + 6C - 6 = -5 $$
$$ -3A - B + 7C = 1 $$
From the first equation:
$$ A = 2 + 2B $$
Substitute $A$ into the above:
$$ -3(2 + 2B) - B + 7C = 1 $$
$$ -6 - 6B - B + 7C = 1 $$
$$ -7B + 7C = 7 $$
$$ -B + C = 1 $$
$$ C = 1 + B $$
Substitute $C$ into $D$:
$$ D = -3(1 + B) + 3 = -3 - 3B + 3 = -3B $$
14. Choose $B = 0$ for simplicity:
$$ C = 1, D = 0, A = 2 $$
15. Therefore, numerators are:
$$ \frac{2x + 1}{2x + 1} - \frac{0x + 0}{x - 3} = \frac{2x + 1}{2x + 1} - 0 $$
But this does not match the original expression. Try $B = 1$:
$$ C = 2, D = -3, A = 4 $$
Check:
$$ (4x + 2)(x - 3) - (1x - 3)(2x + 1) = 4x^2 - 12x + 2x - 6 - (2x^2 + x - 6x - 3) = 4x^2 - 10x - 6 - 2x^2 - x + 6x + 3 = 2x^2 - 5x - 3 $$
This matches perfectly.
16. Final answer:
$$ \frac{4x + 2}{2x + 1} - \frac{x - 3}{x - 3} $$
Simplify the second fraction:
$$ \frac{x - 3}{x - 3} = 1 $$
So the right side is:
$$ \frac{4x + 2}{2x + 1} - 1 $$
This equals the left side expression.
**Answer:** Numerators are $4x + 2$ and $x - 3$ respectively.
Fraction Numerators
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