# Let a and b be the roots of the equation x2 + x + 1 = 0. Then for y �벜 0 in R, y 1 y 1 1 y +a b a +b b +a is equal to:

Question:

Let $\alpha$ and $\beta$ be the roots of the equation $x^{2}+x+1=0$. Then for $\mathrm{y}^{\prime \prime} 0$ in $\mathrm{R},\left|\begin{array}{ccc}\mathrm{y}+1 & \alpha & \beta \\ \alpha & \mathrm{y}+\beta & 1 \\ \beta & 1 & \mathrm{y}+\alpha\end{array}\right|$ is equal to:

1. $\mathrm{y}\left(\mathrm{y}^{2}-1\right)$

2. $\mathrm{y}\left(\mathrm{y}^{2}-3\right)$

3. $\mathrm{y}^{3}$

4. $\mathrm{y}^{3}-1$

Correct Option: 3

JEE Main Previous Year 1 Question of JEE Main from Mathematics Matrices and Determinants chapter.
JEE Main Previous Year April 09, 2019 (I)

Solution:

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