Mathematics · 2021
JEE Main · 18 March 2021, Shift 1 · Q80
A vector a has components 3 p and 1 with respect to a rectangular cartesian system. This system is rotated through a certain angle about the origin…
A vector $\displaystyle \vec{a}$ has components $\displaystyle 3$ p and $\displaystyle 1$ with respect to a rectangular cartesian system. This system is rotated through a certain angle about the origin in the counter clockwise sense. If, with respect to new system, $\displaystyle \overrightarrow{\mathrm{a}}$ has components $\displaystyle \mathrm{p}+1$ and $\displaystyle \sqrt{10}$, then a value of p is equal to:
Official answer
(2)
$\displaystyle -1$
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JEE Main 2021 Mathematics question, with the answer from NTA’s final answer key. Where our answers come from.