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Let $$\alpha$$ be a root of the equation $$(a - c)x^2 + (b - a)x + (c - b) = 0$$, where $$a, b, c$$ are distinct real numbers such that the matrix $$\begin{pmatrix} \alpha^2 & \alpha & 1 \\ 1 & 1 & 1 \\ a & b & c \end{pmatrix}$$ is singular. Then the value of $$\frac{(a - c)^2}{(b - a)(c - b)} + \frac{(b - a)^2}{(a - c)(c - b)} + \frac{(c - b)^2}{(a - c)(b - a)}$$ is
1. Analyze the Quadratic Equation
The given equation is:
$$(a - c)x^2 + (b - a)x + (c - b) = 0$$
Notice that the sum of the coefficients equals zero:
$$(a - c) + (b - a) + (c - b) = a - c + b - a + c - b = 0$$
Whenever the sum of the coefficients of a quadratic equation is zero, $$x = 1$$ is always a root. Thus, one of the roots is:
$$\alpha = 1$$
2. Verify the Matrix Singularity
If $$\alpha = 1$$, the matrix becomes:
$$\begin{pmatrix} 1^2 & 1 & 1 \\ 1 & 1 & 1 \\ a & b & c \end{pmatrix} = \begin{pmatrix} 1 & 1 & 1 \\ 1 & 1 & 1 \\ a & b & c \end{pmatrix}$$
Since the first row and the second row are completely identical, the determinant of the matrix is zero. This confirms that the matrix is **singular** when $$\alpha = 1$$.
3. Simplify the Target Expression
To make the algebraic simplification easier, let us introduce three substitutions:
$$p = a - c$$
$$q = b - a$$
$$r = c - b$$
From our coefficient check in Step 1, we already know that:
$$p + q + r = 0$$
Now, substitute $$p, q,$$ and $$r$$ into the target expression:
$$\text{Value} = \frac{p^2}{qr} + \frac{q^2}{pr} + \frac{r^2}{pq}$$
Find a common denominator for the fractions:
$$\text{Value} = \frac{p^3 + q^3 + r^3}{pqr}$$
4. Apply the Algebraic Identity
Recall the conditional algebraic identity: if $$p + q + r = 0$$, then:
$$p^3 + q^3 + r^3 = 3pqr$$
Substitute this numerator back into our expression:
$$\text{Value} = \frac{3pqr}{pqr} = 3$$
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