Determine the sign (positive or negative) of the given value without use of a calculator.
-$$\cos \left( - \frac { \pi } { 8 } \right)$$
A) Positive
B) Negative

Question

Quizplus · Accepted Answer

The cosine function is positive in the first and fourth quadrants of the unit circle. Since $-\frac{\pi}{8}$ is in the fourth quadrant, $\cos\left(-\frac{\pi}{8}\right)$ is positive.

Determine the Sign (Positive or Negative) of the Given Value cos⁡(−π8)\cos \left( - \frac { \pi } { 8 } \right)cos(−8π​)

Determine the Sign (Positive or Negative) of the Given Value $\cos \left( - \frac { \pi } { 8 } \right)$