Mathematics · 2024
JEE Main · 27 January 2024, Shift 2 · Q18
The position vectors of the vertices A, B and C of a triangle are 2 i -3 j +3 k, 2 i +2 j +3 k and - i + j +3 k respectively. Let l denotes the…
The position vectors of the vertices $\displaystyle \mathrm{A}, \mathrm{B}$ and C of a triangle are $\displaystyle 2 \hat{i}-3 \hat{j}+3 \hat{k}, 2 \hat{i}+2 \hat{j}+3 \hat{k}$ and $\displaystyle -\hat{i}+\hat{j}+3 \hat{k}$ respectively. Let $\displaystyle l$ denotes the length of the angle bisector AD of $\displaystyle \angle \mathrm{BAC}$ where D is on the line segment BC, then $\displaystyle 2 l^2$ equals :
Official answer
From NTA’s final answer key for this paper.
(2)
$\displaystyle 45$
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JEE Main 2024 Mathematics question, with the answer from NTA’s final answer key. Where our answers come from.