有两个交流电e1=Esin(ωt+2π/3),e2=Esin(ωt)迭加后表示为（）
A: 1.414Esin(ωt+π/6),
B: e=Esin(ωt+π/3)
C: e=2Esin(ωt)
D: e=1.732Esin(ωt+π/6),
A: 1.414Esin(ωt+π/6),
B: e=Esin(ωt+π/3)
C: e=2Esin(ωt)
D: e=1.732Esin(ωt+π/6),
举一反三
- 载波为Esinωt的电桥,当单臂输入调制信号ε(t)=AsinΩt时,其输出调幅波的幅值为()。(Ω
- 设\(z = f(x,y)\)，\(x = \sin t\)，\(y = {t^3}\)，则全导数\( { { dz} \over {dt}} = \) A: \({f'_x} \sin t+ 3{t^2}{f'_y}\) B: \({f'_x} \cos t+ {t^2}{f'_y}\) C: \({f'_x} \cos t+ 3{t^2}{f'_y}\) D: \({f'_y} \cos t+ 3{t^2}{f'_x}\)
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