Sum and Difference Formulas

tan (A + B) =

•  $\frac{\tan\ A+\tan B}{1-\tan A\tan B}$  

•  $\frac{\tan A-\tan B}{1+\tan A\tan B}$  

•  $\frac{2\tan A-1}{\tan A\tan B}$  

•  $\frac{2\tan A+1}{\tan A\tan B}$  

Tags

CCSS.HSF.TF.C.9

Use a sum or difference formula to find an exact value of sin 105º

• $\frac{\sqrt{3}}{2}$

• $\frac{-\sqrt{2}-\sqrt{6}}{4}$

• $\frac{\sqrt{2}+\sqrt{6}}{4}$

• $2-\sqrt{3}$

Tags

CCSS.HSF.TF.C.9

Use Sum or Difference Identities to find the exact value of each expression.
cos(75°)

• 1/4
• ( √(6) - √(2) ) / 4
• (√(6) + √(2)) / 4
• (-√(6) - √(2)) / 4

Tags

CCSS.HSF.TF.C.9

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

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

Use sum or difference angles identity to find the exact value for       $\sin\ \left(-15^o\right)$  

•  $\frac{\sqrt{6}+\sqrt{2}}{4}$  

•  $\frac{\sqrt{6}-\sqrt{2}}{4}$  

•  $\frac{\sqrt{2}-\sqrt{6}}{4}$  

•  $-\frac{\sqrt{3}}{2}$  

Tags

CCSS.HSF.TF.C.9