Chapter 5 Review (Honors Precalculus)

Use sum or difference angles identity to find the exact value for  $\cos105^o$  

•  $\frac{\sqrt{6}+\sqrt{2}}{4}$  

•  $\frac{\sqrt{6}-\sqrt{2}}{4}$  

•  $\frac{-\sqrt{6}-\sqrt{2}}{4}$  

•  $\frac{\sqrt{2}-\sqrt{6}}{4}$  

Tags

CCSS.HSF.TF.C.9

Find the exact value of the expression.
cos(20)cos(40) - sin(20)sin(40)

• 1/4
• 1/2
• √(3)/2
• √(3)

Tags

CCSS.HSF.TF.C.9

Solve for  $0\le x<2\pi$  ,  $\sin x=\sin\ 2x$  .

• 0

•  $0,\ \frac{\pi}{3},\ \pi,\ \frac{5\pi}{3}$  

•  $0,\ 2\pi$  

•  $0,\ \frac{\pi}{6},\frac{11\pi}{6},\ 2\pi$  

Tags

CCSS.HSF.TF.B.7

Amanda and Jamie are standing 25 feet apart and spot a bird in the sky between them.  The angle of elevation from Amanda to the bird is 55, and from Jamie to the bird is 63.  How far away is the bird from Amanda?

• 25.23
• 23.19
• 22.15
• 20.85

Tags

CCSS.HSG.SRT.D.10

CCSS.HSG.SRT.D.11

 Which is a correct way to solve the equation

 $\cos x\left(2\cos x-3\right)=0$  

• divide cos x from both sides

• set each factor equal to 0 and solve

• distribute cosx into the parentheses

• guess and hope for the best

Tags

CCSS.HSF.TF.B.7

What is the value of  $\tan\left(2\pi\right)$  

• Undefined

• -1

• 0

• 1

Tags

CCSS.HSF.TF.A.2

What is the value of  $\cot\left(\frac{7\pi}{4}\right)$  

• -1

•  $\frac{\sqrt{2}}{2}$  

•  $-\sqrt{3}$  

• 1

Tags

CCSS.HSF.TF.A.2

 $\sec\left(\frac{\pi}{2}\right)=?$  

• 0

• undefined

• -1

• 1

Tags

CCSS.HSF.TF.A.2

• √3/3
• √3
• 1
• undefined

Tags

CCSS.HSF.TF.A.2

sec 2π/3

• √2∕2

• 1/2

• 2

• -2

Answer explanation

To find sec(2π/3), we first find cos(2π/3), which is -1/2. Since sec is the reciprocal of cos, sec(2π/3) = 1/cos(2π/3) = 1/(-1/2) = -2. Thus, the correct answer is -2.

Tags

CCSS.HSF.TF.A.2