**1. The problem statement, all variables and given/known data**

A 600W carrier wave is modulated to a depth of 75%by a 400Hz sine wave. Find the total antenna power.

(1) 769W

(2) 796W

(3) 679W

(4) 637.5W

**2. Relevant equations**

**3. The attempt at a solution**

I honestly don’t know what to do here. I have tried to find a relevant equation in the chapter related to Communication system present in my textbook but I couldn’t find anything useful. The solution uses the following formula:

$$P_T=P_c\left(1+\frac{m^2}{2}\right)$$

Where can I find the above formula? :confused:

Any help is appreciated. Thanks!

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