Mathematics · 2021
JEE Main · 16 March 2021, Shift 1 · Q67
Let a vector α i +β j be obtained by rotating the vector √ 3 i + j by an angle 45° about the origin in counterclockwise direction in the first…
Let a vector $\displaystyle \alpha \hat{i}+\beta \hat{j}$ be obtained by rotating the vector $\displaystyle \sqrt{3} \hat{i}+\hat{j}$ by an angle $\displaystyle 45$° about the origin in counterclockwise direction in the first quadrant. Then the area of triangle having vertices $\displaystyle (\alpha, \beta),(0, \beta)$ and $\displaystyle (0,0)$ is equal to :
Official answer
(1)
$\displaystyle \frac{1}{2}$
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JEE Main 2021 Mathematics question, with the answer from NTA’s final answer key. Where our answers come from.