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Limit when x tends to 1

Dear friends. I would like to enlist the help of you in this question. I tried to improve the algebric expression, I tried the L'Hospital theorem, but nothing worked.

Grateful for your help. Big hug to everyone.

1 Answers1

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Hint: Let $x=y^6$. We are interested in the limit as $y\to 1$ of $$\frac{1}{2(1-y^3)}-\frac{1}{3(1-y^2)}.$$ Bring to the common denominator $(2)(3)(1-y^2)(1-y^3)$. The numerator is $3(1-y^2)-2(1-y^3)$. There is an obvious factor of $1-y$ on top. Simplify. There is an additional slightly hidden factor of $1-y$.

André Nicolas
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