Limit of arctan(x)-x / arcsin(x)-x as x->0

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The limit of [arctan(x) - x] / [arcsin(x) - x] as x approaches 0 is indeed -2, despite initial calculations suggesting otherwise. The user experienced confusion due to rounding errors from their calculator when evaluating values close to zero. Closer evaluations confirmed that the limit approaches -2 consistently. Arctan and arcsin functions can yield complex results that handheld calculators may not accurately compute. Therefore, the limit is correctly identified as -2, and the discrepancies were due to rounding rather than a miscalculation.
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Homework Statement



I'm asked to find the limit of [arctan(x)-(x)] / [arcsin(x)-(x)] as x--->0

The Attempt at a Solution



So I started plugging in values of x closer and closer to zero. I get:

f(-0.05)= -1.994758
f(-0.01)= -1.999790
f(-0.001)= -2.000012

f(0.05)= -1.994758
f(0.01)= -1.999790
f(0.001)= -2.000024

At first (before I calculated (-0.001 and 0.001) I thought the limit was neg two, but after I calculated -.001 and .001 and got -2.000012 and -2.000024 I'm thrown off. Does the limit not exist, or is my calculator rounding wierdly.

Any help is much appreciated.
 
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This is certainly a rounding error. The limit is -2 as u originally suspected. Here are some closer results:
f(0.001)=−1.995808383
f(-0.001)=−1.995808383
 
so did I compute it wrong? or is that just the way my calculator rounds it?
 
btw, thank you
 
Arcsine and Arctan are relatively complex functions, and handheld calculators don't have the capability of doing a)operations with those complex numbers b)dividing them c)and worse of all, with really really small input values. So it is the way your calculator rounds.
 
thank you for the help
 
Question: A clock's minute hand has length 4 and its hour hand has length 3. What is the distance between the tips at the moment when it is increasing most rapidly?(Putnam Exam Question) Answer: Making assumption that both the hands moves at constant angular velocities, the answer is ## \sqrt{7} .## But don't you think this assumption is somewhat doubtful and wrong?

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