(2012)图1.3-48所示电路中，若电压u(t)=100
sin(10000t)+30sin(30000t)V，则u
(t)为（ ）V。
sin(10000t)+30sin(30000t)V，则u(t)为（ ）V。 - A. 30sin(30000t)
- B. 100sin(10000t)
- C. 30sin(30t)
- D. 100sin(10t)
sin(10000t)+30sin(30000t)V，则u(t)为（ ）V。 sin(30000t)sin(10000t)sin(30t)sin(10t)