Mathematics

Problem

If a unit vector

\vec{a}

makes angles

\frac{\pi}{3}

with

\hat{i}

\frac{\pi}{4}

with

\hat{j}

and

\theta \in (0, \pi)

with

\hat{k}

, then a value of

\theta

is :- (1)

\frac{5\pi}{12}

(2)

\frac{5\pi}{6}

(3)

\frac{2\pi}{3}

(4)

\frac{\pi}{4}