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Vectors & 3D Geometry

JEE Main level, single correct, medium

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Question 4 of 4

If $\vec{a} = \hat{i} + \hat{j}$ and $\vec{b} = \hat{j} + \hat{k}$ , the angle between $\vec{a}$ and $\vec{b}$ is:

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Answer: (B) $\pi/3$

\cos\theta = \frac{\vec{a} \cdot \vec{b}}{|\vec{a}||\vec{b}|} = \frac{1}{\sqrt{2}\sqrt{2}} = \frac{1}{2} \implies \theta = 60^\circ = \pi/3

JEE Main question paper PDF

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JEE Main 2025 Apr 2 Shift 1 question paper

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More Mathematics practice

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JEE Main Mathematics practice question on Vectors & 3D Geometry, with the answer and a step-by-step solution. Scan a question from your own book or paper to get a whiteboard video.

If a⃗=i^+j^\vec{a} = \hat{i} + \hat{j}a=i^+j^​ and b⃗=j^+k^\vec{b} = \hat{j} + \hat{k}b=j^​+k^, the angle between a⃗\vec{a}a and b⃗\vec{b}b is:

JEE Main question paper PDF

More Mathematics practice

If $\vec{a} = \hat{i} + \hat{j}$ and $\vec{b} = \hat{j} + \hat{k}$ , the angle between $\vec{a}$ and $\vec{b}$ is: