Using Double-Angle Identities

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

Using the first identity, find Sin(180)

• 2sin(90)cos(90)
• 2sin(180)cos(180)
• sin(90)cos(90)
• sin(180)cos(180)

Tags

CCSS.HSF.TF.C.9

Using the third identity, find Cos(40)

• 2cos² (40) - 1
• 2cos² (20) - 1
• 2cos² (20) + 1
• 2cos² (40) + 1

Tags

CCSS.HSF.TF.C.9

Using the fourth identity, find Cos(120)

• 1-2sin²(120)
• 1+2sin²(120)
• 1+2sin²(60)
• 1-2sin²(60)

Tags

CCSS.HSF.TF.C.9

Using the first identity, find Sin(180)

• 2sin(90)cos(90)
• 2sin(180)cos(180)
• sin(90)cos(90)
• sin(180)cos(180)

Tags

CCSS.HSF.TF.C.9

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

Using the third identity, find Cos(40)

• 2cos² (40) - 1
• 2cos² (20) - 1
• 2cos² (20) + 1
• 2cos² (40) + 1

Tags

CCSS.HSF.TF.C.9

Using the fourth identity, find Cos(120)

• 1-2sin²(120)
• 1+2sin²(120)
• 1+2sin²(60)
• 1-2sin²(60)

Tags

CCSS.HSF.TF.C.9

Using the fifth identity, find Tan(200)

• 2tan(100)/(1-tan²(100))
• 2tan(200)/(1-tan²(200))
• (1-tan²(100))/2tan(100)
• (1-tan²(100))/2tan(100)

Tags

CCSS.HSF.TF.C.9

Using the second identity, find Cos(2π)

• sin²(π) - cos²(π) 
• cos²(π) - sin²(π)
• cos²(2π) - sin²(2π)
• sin(2π)cos(2π)

Tags

CCSS.HSF.TF.C.9