Limits of a picewise function?

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Homework Help Overview

The discussion revolves around evaluating the limit of a piecewise function as x approaches 2 from the left. The function is defined in segments, with specific expressions for different intervals of x.

Discussion Character

  • Exploratory, Assumption checking, Problem interpretation

Approaches and Questions Raised

  • Participants discuss the limit as x approaches 2 from the left, with one participant asserting the limit is -2 based on the relevant piece of the function. Another participant suggests there may be confusion regarding the expression used in the workbook, indicating a potential printing error.

Discussion Status

The discussion is active, with participants sharing their interpretations and questioning the accuracy of the workbook's answer. There is no explicit consensus, but participants are collaboratively exploring the implications of the piecewise function's definitions.

Contextual Notes

There is mention of previous inaccuracies in the workbook, leading to skepticism about the provided answer. Participants are focused on clarifying the correct interpretation of the function's segments.

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Homework Statement



We're given a piecewise function

g(x) = {
x if x < 1
3 if x = 1
2-x^2 if 1<x<=2
x-3 if x > 2
]

and were asked: lim x-> 2-

Homework Equations



2-x^2 if 1<x<=2
x-3 if x > 2


The Attempt at a Solution




when i drew it out i was getting that the answer is -2 but the workbook says the answer is zero. times have occurred where the answers in this workbook have been wrong, so i would just like someone to verify either one. any help is much appreciated, thanks.
 
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2-x^2 if 1<x<=2 Is all you really need to solve this.. As x approaches 2 from the left, the answer is -2. The other limit = -1 anyway so I don't see how they got 1.

EDIT: They may have thought it's (2-x)^2.. That limit as x->2 is 0..
 
shocklightnin said:

Homework Statement



We're given a piecewise function

g(x) = {
x if x < 1
3 if x = 1
2-x^2 if 1<x<=2
x-3 if x > 2
]

and were asked: lim x-> 2-

Homework Equations



2-x^2 if 1<x<=2
x-3 if x > 2

The Attempt at a Solution



when i drew it out i was getting that the answer is -2 but the workbook says the answer is zero. times have occurred where the answers in this workbook have been wrong, so i would just like someone to verify either one. any help is much appreciated, thanks.
You may have neglected to include the parentheses.

[itex]\displaystyle \lim_{x\to2^-}\left(2-x^2\right)=-2[/itex]

[itex]\displaystyle \lim_{x\to2^-}\left((2-x)^2\right)=0[/itex]
 
thanks to both! and nope, book def. says '(2-x^2) and not (2-x)^2, must be a printing error either in book or ans. key, but thank you!
 

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