Multivariable Limit (Definition of Derivative)

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SUMMARY

The limit of the expression |sin(e^xy) - sin(1)|/(x^2 + y^2)^(1/2) approaches 0 as (x,y) approaches (0,0). This conclusion is based on the fact that e^xy converges to 1 significantly faster than (x^2 + y^2)^(1/2) converges to 0. To establish this limit rigorously, an epsilon-delta proof may be employed, although the user expresses uncertainty about its complexity. The Triangle Inequality may also be relevant in bounding the limit.

PREREQUISITES
  • Understanding of multivariable calculus concepts, specifically limits.
  • Familiarity with the properties of the sine function and its continuity.
  • Knowledge of the epsilon-delta definition of limits.
  • Proficiency in applying the Triangle Inequality in mathematical proofs.
NEXT STEPS
  • Study the epsilon-delta definition of limits in multivariable calculus.
  • Learn how to apply the Triangle Inequality to establish bounds in limits.
  • Explore the behavior of exponential functions near zero, particularly e^xy.
  • Review examples of limits involving trigonometric functions and their derivatives.
USEFUL FOR

Students and educators in multivariable calculus, mathematicians focusing on limit proofs, and anyone seeking to deepen their understanding of derivatives in multiple dimensions.

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Homework Statement


I need to show that |sin(e^xy)-sin(1)|/(x^2+y^2)^1/2 -> 0 as (x,y) -> (0,0)


Homework Equations


Triangle Inequality?


The Attempt at a Solution


I know that this is true, since e^xy -> 1 as (x,y) -> (0,0) much, much faster than (x^2+y^2)^1/2 -> 0 as (x,y) -> (0,0). I don't know how to give this limit an upper bound to prove it though. Otherwise, I guess I could use an epsilon-delta proof, but I think that might be a little much?
 
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Recall that [tex]f^{\prime}(x)=\lim_{x\rightarrow a}\frac{f(x)-f(a)}{x-a}[/tex].
 

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