Use the Formula $a \sin B \theta + b \cos B \theta = \sqrt { a ^ { 2 } + b ^ { 2 } } \sin ( B \theta - C )$

Multiple Choice

Use the formula $a \sin B \theta + b \cos B \theta = \sqrt { a ^ { 2 } + b ^ { 2 } } \sin ( B \theta - C )$ ,where $C = \arctan ( a / b ) , a = 2 , b = 8 , B = 1$ ,to rewrite the trigonometric expression in the following form.​ $y = \sqrt { a ^ { 2 } + b ^ { 2 } } \sin ( B \theta - C )$ ​ $a \sin B \theta + b \cos B \theta$ ​

A) 2 $\cos ( \theta + 0.245 )$
B) $2 \sqrt { 17 }$ $\cos ( \theta - 0.245 )$
C) $2 \sqrt { 17 }$ $\cos ( \theta + 0.245 )$
D) 2 $\cos ( \theta - 0.245 )$
E) 8 $\cos ( \theta - 0.245 )$