\(f(t)=F_n_=_0+\sum_{n=-\infty,n\neq 0}^{n=\infty}F_ne^{jnw_0t}\), where \(F_n=\frac{1}{T}\int_{\tau}^{\tau+T}f(t)e^{-jnw_0t}dt\) and \(F_n_=_0\) is DC component. Power spectrum of signal is defined as \(S_1_1(nw_0)=\left | F_n \right |^{2}\), where \(\left | F_n \right |\) is modulus of complex Fourier coefficient \(F_n\).

In book, they gave us some periodic signal to write it in terms of complex Fourier coefficients and calculate power of first three harmonics. What is power of first three harmonics? Is it \(\left | F_n_=_1 \right |^{2}+\left | F_n_=_2 \right |^{2}+\left | F_n_=_3 \right |^{2}\)?