Radian measure, arc length and exact values Quiz

1. A sector has radius $4$ cm and angle $\frac{\pi}{2}$. What is its area?

• A. $4\pi$ cm$^2$
• B. $2\pi$ cm$^2$
• C. $8\pi$ cm$^2$
• D. $16\pi$ cm$^2$

2. Which is the exact value of $\cos\frac{3\pi}{4}$?

• A. $\frac{\sqrt2}{2}$
• B. $-\frac{\sqrt3}{2}$
• C. $-\frac{\sqrt2}{2}$
• D. $-\frac12$

3. A sector of radius $10$ cm has arc length $15$ cm. Find $\theta$.

• A. $150$ radians
• B. $0.67$ radians
• C. $3$ radians
• D. $1.5$ radians

4. What is the exact value of $\tan\frac{\pi}{3}$?

• A. $\frac{\sqrt3}{3}$
• B. $\sqrt3$
• C. $1$
• D. $\frac{\sqrt3}{2}$

5. The perimeter of a sector of radius $3$ and angle $2$ radians is...

• A. $12$
• B. $6$
• C. $9$
• D. $15$