Mathematics · 2021
JEE Main · 25 July 2021, Shift 2 · Q78
If | a |=2,| b |=5 and | a × b |=8, then | a · b | is equal to:
If $\displaystyle |\overrightarrow{\mathrm{a}}|=2,|\overrightarrow{\mathrm{~b}}|=5$ and $\displaystyle |\overrightarrow{\mathrm{a}} \times \overrightarrow{\mathrm{b}}|=8$, then $\displaystyle |\overrightarrow{\mathrm{a}} \cdot \overrightarrow{\mathrm{b}}|$ is equal to :
Official answer
(4)
$\displaystyle 6$
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JEE Main 2021 Mathematics question, with the answer from NTA’s final answer key. Where our answers come from.