XL=2x2.5=5Ω、Xc=1/(0.5x2)=1ΩZ=√[R^2+(XL-Xc)^2]=√[3^2+(5-1)^2]=5∠53.1ºΩI=Us/Z=(10/√2)∠0º/5∠53.1º=√2∠-53.1ºi(t)=2cos(2t-53.1º) A
