Questão 3318486

\(\frac{\pi^2}{3}\) + \(\frac{\sum_{n\ =\ 1}^{+\ ∞}\ \left(-1\right)^n}{n^2}\) 4 cos nx. sen. nx

π²/3

\(\frac{\sum_{n\ =\ 1}^{+\ ∞}\ \left(-1\right)^N}{n^2}\) 4 cos nx

\(\frac{\pi^2}{3}\) + \(\frac{\sum_{n\ =\ 1}^{+\ ∞}\left(-1\right)^n}{n^2}\) 4 sen nx

\(\frac{\pi^2}{3}\) + \(\frac{\sum_{n\ =\ 1}^{+\ ∞}\left(-1\right)^n}{n^2}\) 4 cos nx