Find First Term: The series starts at n=0, so let's find the first term. For n=0, the term is 0!(cos(1/0!)−1) which is 1(cos(1/1)−1)=0.
General Term for n>0: Now, let's consider the general term for n>0. We have n!(cos(n!1)−1). Since cos(1) is close to 0.54 and decreases as the argument gets smaller, the term cos(n!1) will approach 1 as n increases.
Approaching 1: Because cos(n!1) approaches 1, the expression (cos(n!1)−1) approaches 0. This means that for large n, the terms of the series become very small.
Factorial Growth vs. Cosine: However, we are multiplying by n!, which grows very fast. So we need to check if the factorial growth or the cosine approaching 1 has a stronger effect on the terms.
Factorial Dominance: For large n, n! grows faster than any polynomial function, and since the cosine function is bounded between −1 and 1, the factorial will dominate. This means the terms will not approach 0, and the series will diverge.
Series Divergence: Since the series diverges, it does not have a finite sum. Therefore, we cannot calculate the sum of the series as it does not converge to a specific value.
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