Admittance calculation of a circuit
Two givens:


Admittance is the reciprocal of impedance.
Due to the maximum power theorem, maximum power in the load is
attained when the load is the conjugate match of the output
impedance. This means Rsource=Rload and jsource=-jload


Find the load that draws the maximum power, compute its conjugate (since the source impedance is its conjugate), and take the reciprocal of this conjugate to derive the complex admittance of the circuit's output.