Ch 7.3 and 7.4 Trig Advanced Identities

Expand  $\sin\ \left(33^{o\ }+42^o\right)$  

•  $\sin\ 75^{o\ }$  

•  $\sin\ 33^o\cos42^o+\cos33^o\sin42^o$  

•  $\sin\ 33^o\cos42^o-\cos33^o\sin42^o$  

•  $\cos33^o\cos42^o+\sin33^o\sin42^o$  

Tags

CCSS.HSG.SRT.C.7

Expand  $\cos\ \left(\frac{\pi}{5}+\frac{\pi}{6}\right)$  

•  $\cos\frac{\pi}{5}\cos\frac{\pi}{6}-\sin\frac{\pi}{5}\sin\frac{\pi}{6}\$  

•  $\cos\frac{\pi}{5}\cos\frac{\pi}{6}+\sin\frac{\pi}{5}\sin\frac{\pi}{6}\$  

•  $\cos\ \frac{2\pi}{11}$  

•  $\cos\frac{\pi}{5}\sin\frac{\pi}{6}-\cos\frac{\pi}{5}\sin\frac{\pi}{6}\$  

Tags

CCSS.HSG.SRT.C.8

 $\frac{\tan45^o+\tan30^o}{1-\tan45^o\tan30^o}$  is equivalent to

•  $\tan75^o$  

•  $\tan\ 15^o$  

•  $\frac{\sin45^o}{\cos30^o}$  

•  $\tan90^{o\ }$  

Tags

CCSS.HSF.TF.C.9

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

Write the following expression as the sine, cosine, or tangent of an angle.
cos(175)cos(55)+sin(175)sin(55)

• sin(120)
• cos(120)
• cos(230)
• sin(230)

Tags

CCSS.HSF.TF.C.9

sin2u =

• (sinu)(cosu)
• 2(sinu)(cosu)
• (sinu)^2
• 2(sinu)^2

• 120/169
• 25/169
• 60/169
• 5/13

Using the second identity, find Cos(50)

• sin²(25) - cos²(25) 
• cos²(50) - sin²(50)
• cos²(25) - sin²(25)
• sin²(50) - cos²(50) 

Tags

CCSS.HSF.TF.C.9

If $\sin\theta=\frac{\sqrt{5}}{3}$  , then  $\cos2\theta$  equals

•  $\frac{1}{3}$  

•  $-\frac{1}{3}$  

•  $\frac{1}{9}$  

•  $-\frac{1}{9}$  

Tags

CCSS.HSF.TF.C.9

Use a double-angle or half-angle identity to find the exact value of each expression
sin θ = −3/5 and 3π/2 < θ < 2π Find tan θ/2

• -1/3
• -√3
• √3/3
• -1

Tags

CCSS.HSF.TF.C.9