Limits involving absolute value.

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SUMMARY

The discussion focuses on evaluating limits involving absolute values, specifically the limits \(\lim_{x\rightarrow\infty}\frac{\sin|x|}{x}\) and \(\lim_{x\rightarrow 0}\frac{|x|-|x-2|}{x-1}\). The first limit approaches zero as \(\sin|x|\) is bounded between -1 and 1, leading to \(\frac{\sin|x|}{x}\) converging to zero as \(x\) approaches infinity. The second limit simplifies directly to 2, as the function is continuous at \(x=0\) and can be evaluated by direct substitution.

PREREQUISITES
  • Understanding of limits in calculus
  • Familiarity with absolute value functions
  • Knowledge of continuous functions and their properties
  • Basic trigonometric functions and their behavior
NEXT STEPS
  • Study the properties of limits involving trigonometric functions
  • Explore the concept of continuity in calculus
  • Learn about one-sided limits and their applications
  • Investigate advanced limit techniques such as L'Hôpital's Rule
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Students of calculus, mathematics educators, and anyone interested in mastering limit evaluation techniques involving absolute values and trigonometric functions.

singedang2
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[tex]\lim_{x\rightarrow\infty}\frac{\sin|x|}{x}[/tex]

[tex]\lim_{x\rightarrow 0}\frac{|x|-|x-2|}{x-1}[/tex]

thanks!
 
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ok hello people this is my first post! woot! okily i gtg to da shops now, so basically i just answer ur post bout da limits...ok well the first one, sin lxl divided by x, approaching infinity, well you see, think about it this way, sin lxl has to be between -1, and 1, as we know. now, 1/infinty= 0
-1/infinity=-0=0, anything inbetween will also equal zero, except zero it self, but as u can see, the limit as it approaches that is also zero, i know I am not very clear..ok basically its zero..and the 2nd one, a little easier :D well basically people use limits to find out wat the value something wud approach at an asymtote or a discontinous point. however, in this case, there is no discontinuity at point zero, so you can just sub it straight in and you'll be fine. so its (0 - l0-2l)/(0-1)= (0- +2)/-1= 2

i know my layout is bad, i hope u get da gist of it..
 
For the first, since x is approaching infinity, x is always positive and |x|= x.

For the second, do the two onesided limits: For x close to 0 and x> 0, |x|= x and |x- 2|= 2- x ( x is close to 0 so x< 2, x- 2 is negative). For x close to 0 and x< 0, |x|= -x and |x-2|= 2- x (x is still less than 2).

(Gib Z is correct- since the second function is continuous at x= 0, you can just substitute x= 0 but it might be that you want to find the limit in order to show that the function is continuous.)
 

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