A new solution and its numerical emulation for the nonlinear RLC circuit are given. The state variable of the circuit is expressed as the simple harmonic function of the phase angle. The determination for the first derivative of the phase angle about the time are used to solve the state equations. The relation of the time independent variable with the middle variable of the phase angle is shown as the integral for the reciprocal of the response frequency. The numerical values

including  the phase portraits

the time-distance curve

the phase-distance curve

and the time-range curve

and the phase-range curve

and the range-frequency curve

and the phase-frequency curve and the response period

are computed. The results are in good agreement with the numerical integral method.