True or false, justify your answer(adsbygoogle = window.adsbygoogle || []).push({});

1) If [tex]\sum_{n=1}^\infty a_n[/tex] converges, then [tex]\sum_{n=1}^\infty (-1)^n \ a_n[/tex] converges.

2) If [tex]\sum_{n=1}^\infty a_n[/tex] converges and [tex]\sum_{n=1}^\infty (-1)^n \ a_n[/tex] converges, then [tex]\sum_{n=1}^\infty a_n[/tex] converges absolutely.

3) If [tex]\sum_{n=1}^\infty a_n[/tex] converges absolutely, then [tex]\sum_{n=1}^\infty (-1)^n \ a_n[/tex] converges absolutely.

Can anybody help me with this one?

Thanks in advance

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# Homework Help: 3 true or false

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