Problem:
Simplify the following expression $\left(4 \left(-\cos \left(\frac{\pi }{15}\right)-i \sin \left(\frac{\pi }{15}\right)\right)\right)^3$
Answer:
$64 \left(\frac{1}{4} \left(-1-\sqrt{5}\right)-i \sqrt{\frac{5}{8}-\frac{\sqrt{5}}{8}}\right)$
{'source': 'AMPS', 'file': 'amps/mathematica/algebra/complex_raised_to_exponent/5058.txt'}