Chapter 12.5, Problem 21MCQ

To determine

To find: In which quadrant does the terminal side of $\theta$ lies.

Answer to Problem 21MCQ

Terminal of $\theta$ lies in Quadrant I or Quadrant IV

Explanation of Solution

Given information:

  $\cos \theta >0$

Given

  $\cos \theta >0$

We know

All trigonometric functions are positive in Quadrant-I

In Quadrant II only sine and cosecant functions are positive

In Quadrant III tan and cot functions are positive

In Quadrant IV cosine and secant functions are positive.

As we need

  $\cos \theta >0$

This will be possible only in Quadrant I and Quadrant IV.

Therefore,

Terminal of $\theta$ lies in Quadrant I or Quadrant IV