ExamBro
ExamBro
CUET · MATHS · PYQ PAPER 2025

If \(\vec{p}\) and \(\vec{q}\) are two unit vectors such that \(|\vec{p}+\vec{q}|=\sqrt{2}\), then which of the following are correct?
(A) \(|\vec{p}|=|\vec{q}|=1\)
(B) \(\vec{p}\) and \(\vec{q}\) are orthogonal vectors
(C) \(\vec{p}\) and \(\vec{q}\) are collinear vectors
(D) \((4 \vec{p}-\vec{q}) \cdot(2 \vec{p}+\vec{q})=7\)
Choose the correct answer from the options given below :

  1. A (A) and (C) only
  2. B (B) and (C) only
  3. C (A), (C) and (D) only
  4. D (A), (B) and (D) only
Verified Solution

Answer & Solution

Correct Answer

(D) (A), (B) and (D) only

Step-by-step Solution

Detailed explanation

\( |\vec{p}|=1, |\vec{q}|=1 \) \( |\vec{p}+\vec{q}|^2 = |\vec{p}|^2 + |\vec{q}|^2 + 2\vec{p}\cdot\vec{q} \) \( (\sqrt{2})^2 = 1^2 + 1^2 + 2\vec{p}\cdot\vec{q} \) \( 2 = 1 + 1 + 2\vec{p}\cdot\vec{q} \) \( 0 = 2\vec{p}\cdot\vec{q} \Rightarrow \vec{p}\cdot\vec{q} = 0 \) Thus, (A)…
From CUET
Explore more questions on app