Mathematics · 2019
JEE Main · 10 January 2019, Shift 2 · Q65
The number of values of θ ∈(0, π) for which the system of linear equations x+3 y+7 z=0; -x+4 y+7 z=0; ( sin 3 θ) x+( cos 2 θ) y+2 z=0 has a…
The number of values of $\displaystyle \theta \in(0, \pi)$ for which the system of linear equations
$$\begin{aligned}
& x+3 y+7 z=0 \\
& -x+4 y+7 z=0 \\
& (\sin 3 \theta) x+(\cos 2 \theta) y+2 z=0
\end{aligned}
$$
has a non-trivial solution, is :
Official answer
(3)
two
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JEE Main 2019 Mathematics question, with the answer from NTA’s final answer key. Where our answers come from.