We know that
$\displaystyle-\frac{2}{1+4x^2}=-2+8x^2-32x^4+128x^6+...$
for $x\in\left(-\dfrac{1}{2},\dfrac{1}{2}\right)$.
**Using this fact, find the function that corresponds to the following series.**
$\displaystyle -2x+\frac{{8}}{3}x^3-\frac{32}{5}x^5+\frac{128}{7}x^7+...$
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