Sum/difference and double/half angle identities

Use a double-angle or half-angle identity to find the exact value of each expression

cos θ = 4/5 and 270° < θ < 360°Find sin 2θ

• -1/5

• 24/25

• -24/25

• -25/24

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

Use a double-angle identity to find the exact value of each expression
cos θ = 4/5 and 270° < θ < 360°
Find sin 2θ

• -1/5
• 24/25
• -24/25
• -25/24

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

Find the exact value of sin 2x if sin x = 12/13 and x is in the first quadrant. 

• 120/169
• 25/169
• 60/169
• 5/13

Use the information about the angle θ, 0≤θ<2π to find the exact value of
sin (2θ)
1. sin θ= 3/5 , 0<θ<π/2

• 24/7
• 7/25
• 24/25
• 1/2

sin2u =

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

Find the exact value of sin 2x if sin x = 12/13 and x is in the first quadrant. 

• 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) 

 $\cos70^o\cos40^o-\sin70^o\sin40^o\$  is equivalent to

•  $\cos30^o$  

•  $\cos70^{o\ }$  

•  $\cos110^o$  

•  $\sin70^{o\ }$