Q. The general value of $\theta$ in the equation $\cos{\theta = \frac{1}{\sqrt{2}}},\tan{\theta = - 1}$ is
A) $2n\pi \pm \frac{\pi}{6},\ n \in I$
B) $2n\pi \pm \frac{7\pi}{4},\ n \in I$
C) $n\pi + ( - 1)^{n}\frac{\pi}{3},\ n \in I$
D) $n\pi + ( - 1)^{n}\frac{\pi}{4},\ n \in I$
Explanation
(b)
Since, $\cos\theta$ is positive and $\tan\theta$ is negative, which lies in IVth quadrant.
$\therefore\ \ \ \theta = 315{^\circ} = \frac{7\pi}{4}$
$\therefore$ The general value of $\theta$ is $2n\pi + \frac{7\pi}{4},\ \ n \in I$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.