电容、电阻并联后的阻抗为：Z1=100*-(j100)/(100-j100)=70.7∠-45°=50-j50整个电路阻抗为：Z=Z1+j100=50+j50=70.7∠45°相量U1=2∠0°x70.7∠45°=141.4∠45°V电路的有功功率P=2x141,4cos45°=200W
