Mathematics · 2019
JEE Main · 12 January 2019, Shift 1 · Q65
An ordered pair (α, β) for which the system of linear equations (1+α) x+β y+z=2; α x+(1+β) y+z=3; α x+β y+2 z=2 has a unique solution, is:
An ordered pair $\displaystyle (\alpha, \beta)$ for which the system of linear equations
$$\begin{aligned}
& (1+\alpha) x+\beta y+z=2 \\
& \alpha x+(1+\beta) y+z=3 \\
& \alpha x+\beta y+2 z=2
\end{aligned}
$$
has a unique solution, is :
Official answer
(4)
$\displaystyle (2,4)$
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JEE Main 2019 Mathematics question, with the answer from NTA’s final answer key. Where our answers come from.