If $\alpha$, $\beta$ are zeroes of the polynomial $x^2 - 1$, then the value of $(\alpha + \beta)$ is :

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## Model Answer **(d) 0** For $x^2 - 1$, we have $a = 1,\ b = 0,\ c = -1$. So $\alpha + \beta = \dfrac{-b}{a} = \dfrac{0}{1} = 0$. Source: Chapter 2, Section 2.3 ## Explanation Use the formula $\alpha + \beta = \frac{-b}{a}$. Since the polynomial $x^2 - 1$ has no $x$ term, $b = 0$, making the sum of zeroes zero. You can verify: zeroes are $+1$ and $-1$, and $1 + (-1) = 0$.

Mathematics — CBSE Class 10 board question