# Should you find theta? (II)

Geometry Level 4

$\large x_n=2^n \cos n\theta$

For the given sequence we know that $\large x_2=-\frac{28}{9}$ and $\large x_3=- \frac{184}{27}.$

If $x_5=\dfrac{A}{B},$ where $A$ and $B$ are coprime positive integers, find $A+B.$

See Part 1.

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