Use the sum-to-product formulas to rewrite the sum or difference as a product.
Cos 3$\theta$ + cos 8$\theta$

A) $\cos \frac { 11 \theta } { 2 } \cos \frac { 5 \theta } { 2 }$
B) $2 \cos \frac { 11 \theta } { 2 } \sin - \frac { 5 \theta } { 2 }$
C) $2 \sin \frac { 11 \theta } { 2 } \sin \frac { 5 \theta } { 2 }$
D) $\cos - \frac { 11 \theta } { 2 } \cos \frac { 5 \theta } { 2 }$
E) $2 \cos \frac { 11 \theta } { 2 } \cos - \frac { 5 \theta } { 2 }$

Question

Use the sum-to-product formulas to rewrite the sum or difference as a product.  
Cos 3$\theta$ + cos 8$\theta$
 
A)  $\cos \frac { 11 \theta } { 2 } \cos \frac { 5 \theta } { 2 }$
B)  $2 \cos \frac { 11 \theta } { 2 } \sin - \frac { 5 \theta } { 2 }$
C)  $2 \sin \frac { 11 \theta } { 2 } \sin \frac { 5 \theta } { 2 }$
D)  $\cos - \frac { 11 \theta } { 2 } \cos \frac { 5 \theta } { 2 }$
E) $2 \cos \frac { 11 \theta } { 2 } \cos - \frac { 5 \theta } { 2 }$

Quizplus · Accepted Answer

The Answer of Use the sum-to-product formulas to rewrite the sum or difference as a product.  
Cos 3$\theta$ + cos 8$\theta$
 
A)  $\cos \frac { 11 \theta } { 2 } \cos \frac { 5 \theta } { 2 }$
B)  $2 \cos \frac { 11 \theta } { 2 } \sin - \frac { 5 \theta } { 2 }$
C)  $2 \sin \frac { 11 \theta } { 2 } \sin \frac { 5 \theta } { 2 }$
D)  $\cos - \frac { 11 \theta } { 2 } \cos \frac { 5 \theta } { 2 }$
E) $2 \cos \frac { 11 \theta } { 2 } \cos - \frac { 5 \theta } { 2 }$

Use the Sum-To-Product Formulas to Rewrite the Sum or Difference θ\thetaθ

Use the Sum-To-Product Formulas to Rewrite the Sum or Difference $\theta$