- 34

- 0

**1. Homework Statement**

Let s be the sum of the alternating series [tex]\sum[/tex](from n=1 to [tex]\infty[/tex])(-1)

^{n+1}a

_{n}with n-th partial sum s

_{n}. Show that |s - s

_{n}| [tex]\leq[/tex]a

_{n+1}

**2. Homework Equations**

I know about Cauchy sequences, the Ratio test, the Root test

**3. The Attempt at a Solution**

I really have no idea where i'm meant to start with this question. I didn't know whether I thne have to take more partial sums i.e. partial sums of the n-th partial sum and work with it from there, or something else. I would be really grateful if someone could help me out.