The LCD is 6. Multiply the entire expression by 6, and then divide the result by 6:
6 [ 6(x^2-1) * 6x-1/6(x+1) ]
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6
When expanded and simplified, we get:
(36x^2 - 36)*6x - (x+1)
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6
or:
216x^3 - 216x - x - 1
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6
Combining the two x-terms:
216x^3 - 217x -1
----------------------- (answer)
6
