JEE Mains · Maths · STD 12 - 10. vector algebra
Let \(\vec{a}\) and \(\vec{b}\) be two vectors. Let \(|\vec{a}|=1,|\vec{b}|=4\) and \(\vec{a} \cdot \vec{b}=2\). If \(\vec{c}=(2 \vec{a} \times \vec{b})-3 \vec{b}\), then the value of \(\overrightarrow{ b } \cdot \overrightarrow{ c }\) is
- A \(-24\)
- B \(-48\)
- C \(-84\)
- D \(-60\)
Answer & Solution
Correct Answer
(B) \(-48\)
Step-by-step Solution
Detailed explanation
\(\overrightarrow{ c }=(2 \overrightarrow{ a } \times \overrightarrow{ b })-3 \overrightarrow{ b }\)…
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