What is the Maclaurin series for f(x)=cos(x)f(x) = \cos(x)f(x)=cos(x)?
∑n=0∞(−1)nx2n(2n)!\sum_{n=0}^{\infty} (-1)^n \frac{x^{2n}}{(2n)!}∑n=0∞(−1)n(2n)!x2n
∑n=0∞x2n(2n)!\sum_{n=0}^{\infty} \frac{x^{2n}}{(2n)!}∑n=0∞(2n)!x2n
∑n=0∞(−1)nxnn!\sum_{n=0}^{\infty} (-1)^n \frac{x^{n}}{n!}∑n=0∞(−1)nn!xn
∑n=0∞(−1)nx2n+1(2n+1)!\sum_{n=0}^{\infty} (-1)^n \frac{x^{2n+1}}{(2n+1)!}∑n=0∞(−1)n(2n+1)!x2n+1