Class CBSE Class 12 Mathematics Vector Algebra Q #1727
KNOWLEDGE BASED 1 Marks 2026 AISSCE(Board Exam) MCQ SINGLE
If $(\vec{a}+\vec{b}).(\vec{a}-\vec{b})=198$ and $|\vec{a}|=10|\vec{b}|$, then :
(A) $|\vec{a}|=\sqrt{2}$
(B) $|\vec{b}|=\sqrt{2}$
(C) $|\vec{b}|=10\sqrt{2}$
(D) $|\vec{a}|=\frac{10}{\sqrt{2}}$