For the amplitude-modulated signal x_AM(t) = 10(1 + 0.5 sin 2πf_m t) cos 2πf_c t, with f_m < B, the average power contained in the sidebands is

25
12.5
6.25
3.125

Correct answer: 3.125

Solution

The average power in the sidebands of an amplitude-modulated signal can be calculated using the modulation index and the carrier power. In this case, the modulation index is 0.5, and the carrier power is 25, leading to a sideband power of 3.125.

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