Question

0 <x<180° then cos x/2 is positive or negative ​

Answer 1

Answer:

It's negative

Step-by-step explanation:

In the third quadrant (from 180 to 270 degrees), the arm is positive while x and y are both negative. So sin m, cos m are both negative values while tan m is positive in the third quadrant. In the fourth quadrant (from 270 to 360 or 0 degrees), the arm and x are positive while y is negative.

Answer 2

Answer :

• cos x/2 is positive

Explanation :

Since the value of x lies between 0 to 180° according to the question, value of x/2 will be ranging from 0 to 90°, we know that all the trigonometric functions are positive in first quadrant i.e. from angle 0° to 90°. Hence cos x/2 is always positive when 0 < x < 180°.

More :-

• sin A and cosec A are positive in 1st as well as 2nd quadrant.

• tan A and cot A are positive in 1st as well as 3rd quadrant.

• cos A and sec A are positive in 1st as well as 4th quadrant.