I tried rationalizing this [multiplying and dividing by (n+32)13+(n+12)13 but then the numerator contains terms of power 23. So I couldn't move forward.
What are methods to evaluate this?
PS : While typing this question I got this,
(n+32)13−(n+12)13=(1+32n)13−(1+12n)13n−13.
Now I apply L'hospital rule and get,
limn→∞[(n+32)13−(n+12)13]=limn→∞12n23[(1+32n)−23−(1+12n)−23]=0.
Am I right?
Answer
HINT:
You should multiply and divide by (n+32)23+(n+32)13(n+12)13+(n+12)23 to rationalize this as
a3−b3=(a−b)(a2+ab+b2)
The rest should be simple...
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