WBJEE · Maths · Vector Algebra
If the sum of two unit vectors is a unit vector, then the magnitude of their difference is
- A \(\sqrt{2}\) units
- B 2 units
- C \(\sqrt{3}\) units
- D \(\sqrt{5}\) units
Answer & Solution
Correct Answer
(C) \(\sqrt{3}\) units
Step-by-step Solution
Detailed explanation
\(\begin{aligned} &\text { Let a and } \mathbf{b} \text { are two unit vectors. }\\ &\text { Then, } \quad|\mathbf{a}+\mathbf{b}|=1\\ &\Rightarrow \quad|\mathbf{a}+\mathbf{b}|^{2}=1 \end{aligned}\) \(\Rightarrow \quad(a+b) \cdot(a+b)=1\)…
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