Help pls!?!?!?!!! This is algebra 2

Mathematics

1 answer:

Tresset [83]2 years ago

5 0

$\boxed{\sf a_n=\dfrac{(-1)^n}{5n}}$

a:-

$\\ \sf\longmapsto a_1=\dfrac{(-1)^1}{5(1)}$

$\\ \sf\longmapsto a_1=\dfrac{-1}{5}$

$\\ \sf\longmapsto a_1=-5$

b:-

$\\ \sf\longmapsto a_4=\dfrac{(-1)^4}{5(4)}$

$\\ \sf\longmapsto a_4=\dfrac{1}{20}$

c:-

$\\ \sf\longmapsto a_{30}=\dfrac{(-1)^{30}}{5(30)}$

$\\ \sf\longmapsto a_{30}=\dfrac{1}{150}$

d:-

$\\ \sf\longmapsto a_{19}=\dfrac{(-1)^{19}}{5(19)}$

$\\ \sf\longmapsto a_{19}=\dfrac{-1}{95}$

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