Answer
$\frac{61}{36}$
Work Step by Step
$\sum_{k=1}^{3} (-1)^{k+1}\frac{k+1}{k^2}\\=(-1)^{1+1}\frac{1+1}{1^2}+(-1)^{2+1}\frac{2+1}{2^2}+(-1)^{3+1}\frac{3+1}{3^2}\\=(-1)^{2}\frac{2}{1}+(-1)^{3}\frac{3}{4}+(-1)^{4}\frac{4}{9}\\=\frac{61}{36}$
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