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Mathematics · 2025 · 1 mark
CBSE 2025 · Region 5 · Set 1 · Q18
The respective values of | a | and | b |, if given ( a - b ) ·( a + b )=512 and | a |=3| b |, are:
The respective values of $\displaystyle |\overrightarrow{\mathrm{a}}|$ and $\displaystyle |\overrightarrow{\mathrm{b}}|$, if given $\displaystyle (\vec{\mathrm{a}}-\vec{\mathrm{b}}) \cdot(\vec{\mathrm{a}}+\vec{\mathrm{b}})=512$ and $\displaystyle |\vec{\mathrm{a}}|=3|\vec{\mathrm{b}}|$, are:
Official answer
(C)
$\displaystyle 24$ and $\displaystyle 8$
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