Question 596010
# 1

you can keep going and factor x^2-4 into (x-1)(x+1)


So the final answer is 15x(x-1)(x+1)


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# 2

Correct

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# 3

Correct

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# 4


<img src="http://latex.codecogs.com/png.latex?\LARGE \{...,-3,-1,1,3,5,7,...\} = \{2k+1 | k\in\mathbb{Z}\}" title="\LARGE \{...,-3,-1,1,3,5,7,...\} = \{2k+1 | k\in\mathbb{Z}\}" />