Let be a vector which makes an angle of with a unit vector

MATHEMATICS · Single correct · CBSE · Mathematics · Vector Algebra · Vector Algebra

Problem

Let

\mathbf{a} = \hat{i}

be a vector which makes an angle of

120^\circ

with a unit vector

\mathbf{b}

. Then, the unit vector

(\mathbf{a} + \mathbf{b})

is (1)

-\frac{1}{2}\hat{i} + \frac{\sqrt{3}}{2}\hat{j}

(2)

-\frac{\sqrt{3}}{2}\hat{i} + \frac{1}{2}\hat{j}

(3)

\frac{1}{2}\hat{i} + \frac{\sqrt{3}}{2}\hat{j}

(4)

\frac{\sqrt{3}}{2}\hat{i} - \frac{1}{2}\hat{j}