ComplexNumber.pow() doesn't work as expected for a negative power

I have mathematical operation:
ComplexNumber cosSinPow=ComplexNumber.multiply(omega, ComplexNumber.pow(coSin, -k * j));

where:
k=8;
j=1;
omega=1.0+0.0i;
coSin=0.9917900138232462+0.127877161684506i;

Expected result: 0.51839256831052 -0.85514276300535 i
Current result: 0.9917900138232462+0.127877161684506i

Look at the ComplexNumber.pow() method implementation, likely in the main library class. The issue shows a specific case where a negative exponent leads to an incorrect result. Start by writing a test with the provided numbers to reproduce the bug, then examine the power calculation logic for handling negative exponents. Check if the method correctly computes reciprocals or uses the polar form (magnitude and argument).

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