题目
已知两个同频率、同方向的简谐振动：x_(1)=Acos(omega t+(3pi)/(4))，x_(2)=3Acos(omega t-(pi)/(4))（SI）。则合振动的振动方程应为【 】A. x=4Acos(omega t-(pi)/(4))B. x=2Acos(omega t-(pi)/(4))C. x=2Acos(omega t+(3pi)/(4))D. x=4Acos(omega t+(pi)/(2))
已知两个同频率、同方向的简谐振动：$x_{1}=A\cos(\omega t+\frac{3\pi}{4})$，$x_{2}=3A\cos(\omega t-\frac{\pi}{4})$（SI）。则合振动的振动方程应为【 】
A. $x=4A\cos(\omega t-\frac{\pi}{4})$
B. $x=2A\cos(\omega t-\frac{\pi}{4})$
C. $x=2A\cos(\omega t+\frac{3\pi}{4})$
D. $x=4A\cos(\omega t+\frac{\pi}{2})$
题目解答
答案
B. $x=2A\cos(\omega t-\frac{\pi}{4})$